Fractures of the Proximal Femur: Improving Outcomes E-Book
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Fractures of the Proximal Femur: Improving Outcomes, by Dr. James P. Waddell, helps you maximize clinical outcomes when addressing the challenges, complications, and treatment of patients with hip fractures. Match pre-operative assessment, surgical techniques, post-operative management, and more to the specific lifestyle factors of each patient in order to achieve optimal results. Apply state-of-the-art techniques and protocols with the visual help of operative videos as well as more than 500 surgical line drawings and photographs in print and online at www.expertconsult.com.

  • See how to perform each technique step by step with operative videos and online access at www.expertconsult.com.
  • Review surgical techniques such as pinning, plating/intramedulary devices, and total hip replacement implants, and get a greater understanding of deep vein thrombosis and pulmonary embolism prevention.
  • Brush up on related topics including epidemiology, osteoporosis, co-morbidities, evidence-based post-op, and rehabilitation protocols.
  • Get the advice of expert contributors worldwide who detail best practices in prophylaxis, surgical technique, and rehabilitation.

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Date de parution 24 septembre 2010
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EAN13 9781437736311
Langue English
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Fractures of the Proximal Femur
Improving Outcomes

James P. Waddell, MD, FRCSC
Professor of Orthopaedic Surgery, University of Toronto School of Medicine, Division of Orthopaedic Surgery, St. Michaels Hospital, Toronto, Ontario, Canada
Saunders
Front matter
Fractures of the Proximal Femur: Improving Outcomes

Fractures of the Proximal Femur

Improving Outcomes
James P. Waddell, MD, FRCSC , Professor of Orthopaedic Surgery, University of Toronto School of Medicine, Division of Orthopaedic Surgery, St. Michaels Hospital, Toronto, Ontario, Canada
Copyright

1600 John F. Kennedy Blvd.
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Philadelphia, PA 19103-2899
Fractures of the Proximal Femur: Improving Outcomes
ISBN: 978-1-4377-0695-6
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. Details on how to seek permission, further information about the Publisher’s permissions policies and our arrangements with organizations such as the Copyright Clearance Center and the Copyright Licensing Agency, can be found at our website: www.elsevier.com/permissions .
This book and the individual contributions contained in it are protected under copyright by the Publisher (other than as may be noted herein).


Notice
Knowledge and best practice in this field are constantly changing. As new research and experience broaden our understanding, changes in research methods, professional practices, or medical treatment may become necessary.
Practitioners and researchers must always rely on their own experience and knowledge in evaluating and using any information, methods, compounds, or experiments described herein. In using such information or methods they should be mindful of their own safety and the safety of others, including parties for whom they have a professional responsibility.
With respect to any drug or pharmaceutical products identified, readers are advised to check the most current information provided (i) on procedures featured or (ii) by the manufacturer of each product to be administered, to verify the recommended dose or formula, the method and duration of administration, and contraindications. It is the responsibility of practitioners, relying on their own experience and knowledge of their patients, to make diagnoses, to determine dosages and the best treatment for each individual patient, and to take all appropriate safety precautions.
To the fullest extent of the law, neither the Publisher nor the authors, contributors, or editors assume any liability for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions, or ideas contained in the material herein.
Chapter 10, “Trochanteric Fractures: Sliding Hip Screw,” and Chapter 12, “Complications in Trochanteric Fractures,” by Jan Bartoníček. Jan Bartoníček retains copyright to text.
Library of Congress Cataloging-in-Publication Data
Fractures of the proximal femur : improving outcomes / [edited by] James P. Waddell. -- 1st ed.
p. ; cm.
Includes bibliographical references.
ISBN 978-1-4377-0695-6 (pbk. : alk. paper) 1. Femur--Fractures. I. Waddell, J. P. (James P.)
[DNLM: 1. Femoral Fractures--surgery. 2. Hip Fractures--surgery. WE 855]
RD560.F73 2011
617.1’58--dc22
2010029515
Acquisitions Editor: Kim Murphy
Developmental Editor: Joan Ryan
Publishing Services Manager: Anne Altepeter
Team Manager: Radhika Pallamparthy
Senior Project Manager: Doug Turner
Project Manager: Preethi Varma
Designer: Louis Forgione
Printed in People’s Republic of China
Last digit is the print number: 9 8 7 6 5 4 3 2 1
Contributors

Jan Bartoníček, MD, Professor of Orthopaedic Surgery, Orthopaedic Department, Third Faculty of Medicine, Charles University and University Hospital Královské Vinohrady, Prague, Czech Republic

Peter Biberthaler, MD, Associate Professor, Consultant Trauma and Orthopedic Surgery, Department of Surgery—Downtown, Ludwig-Maximilians-University Munich, Munich, Germany

Earl R. Bogoch, MD, FRCSC, Medical Director, Mobility Program, Li Ka Shing Knowledge Institute and the Mobility Program Clinical Research Unit, St. Michael’s Hospital, Professor, Department of Surgery, University of Toronto, Toronto, Ontario, Canada

Bok Man Chan, MBBS, FRCPC, Director, Acute Pain Management, Pain Management Service, Department of Anaesthesia, St. Michael’s Hospital, Toronto, Ontario, Canada

Angela M. Cheung, MD, PhD, FRCPC, Associate Professor, Divisions of General Internal Medicine and Endocrinology, Department of Medicine, Director, Centre of Excellence in Skeletal Health Assessment, Joint Department of Medical Imaging, Director, University Health Network Osteoporosis Program, University of Toronto, Toronto, Ontario, Canada

Judy Ann David, MD, Dip NB, Associate Professor, Physical Medicine and Rehabilitation, Tamilnadu Dr. MGR Medical University, Chennai, Tamilnadu, India, Associate Professor, Physical Medicine and Rehabilitation, Christian Medical College Hospital, Vellore, Tamilnadu, India

Pavel Douša, MD, PhD, Assistant Professor, Orthopaedic and Traumatology Department, Third Medical School, Charles University, Orthopedi, St University Hospital Králoské Vinohrady, Prague, Czech Republic

Victoria I.M. Elliot-Gibson, MSc, Research Coordinator, Li Ka Shing Knowledge Institute and the Mobility Program Clinical Research Unit, St. Michael’s Hospital, Toronto, Ontario, Canada

John F. Flannery, MD, FRCPC, Medical Director, MSK Rehabilitation Program, Toronto Rehabilitation Institute, Toronto, Ontario, Canada, Consultant Physiatrist, University Health Network, Mount Sinai Hospital and St. John’s Rehabilitation Hospital, Toronto, Ontario, Canada

Dagmar K. Gross, MSc, President, MedSci Communications & Consulting Co., Glace Bay, Nova Scotia, Canada

Gordon A. Higgins, BSc, MBChB, MRCS (Eng), FRCS (Tr & Orth), Orthopaedic Consultant, Torbay Hospital, South Devon Healthcare NHS Foundation Trust, Chief, The Torbay Hip and Knee Clinic, Lawes Bridge, Torquay, United Kingdom

Aaron Hong, BSc, MSc, MD, FRCPC, Staff Anesthesiologist, Department of Anesthesia, St. Michael’s Hospital, University of Toronto, Toronto, Ontario, Canada

Hans J. Kreder, MD, MPH, FRCSC, Professor, University of Toronto, Orthopaedic Surgery and Health Policy Management and Evaluation, Chief, Holland MSK Program, Marvin Tile Chair & Chief, Division of Orthopaedic Surgery, Sunnybrook Health Science Center, Toronto, Ontario, Canada

Florian Kutscha-Lissberg, MD, Trauma Consultant, Department of Trauma Surgery, Medical University of Vienna, Vienna, Austria

Paul R.T. Kuzyk, BSc (Eng.), MASc, MD, FRCSC, Clinical Fellow, Division of Orthopaedics, Department of Surgery, University of Toronto, Toronto, Ontario, Canada

Peter Leung, MD, FRCPC, Director, Chronic Pain Management, Pain Management Service, Department of Anaesthesia, St. Michael’s Hospital, Toronto, Ontario, Canada

Rhona McGlasson, BScPT, MBA, Project Director, Holland Orthopaedic and Arthritis Centre, Sunnybrook Health Sciences Centre, Implementation Branch, Access to Care Wait Times, Ontario Ministry of Health and Long-Term Care, Toronto, Ontario, Canada

Janet E. Legge McMullan, RN, BScN, MN, Project Director, Holland Orthopaedic and Arthritis Centre, Sunnybrook Health Sciences Centre, Implementation Branch, Access to Care Wait Times, Ontario Ministry of Health and Long-Term Care, Toronto, Ontario, Canada

Mirek M. Otremba, MD, BSc, FRCPC, Assistant Professor of Medicine, University of Toronto, Director, Medical Consultation Service, Mount Sinai Hospital, Toronto, Ontario, Canada

Dawn H. Pearce, MD, FRCPC, Musculoskeletal Radiologist, Department of Radiology, St Michael’s Hospital, Toronto, Ontario, Canada

Patrick Platzer, MD, Trauma Consultant, Department of Trauma Surgery, Medical University of Vienna, Vienna, Austria

Tania Di Renna, MD, Department of Anesthesiology, The Ottawa Hospital, Ottawa, Ontario, Canada

Andreas H. Ruecker, MD, Lead Senior Consultant, Trauma, Hand and Reconstructive Surgery, University Hospital Hamburg— Eppendorf, Hamburg, Germany

Emil H. Schemitsch, MD, FRCSC, Head Division of Orthopaedic Surgery, St. Michael’s Hospital, Professor of Surgery, University of Toronto, Toronto, Ontario, Canada

Gerhild Thalhammer, MD, Trauma Consultant, Department of Trauma Surgery, Medical University of Vienna, Vienna, Austria

James P. Waddell, MD, FRCSC, Professor of Orthopaedic Surgery, University of Toronto School of Medicine, Division of Orthopaedic Surgery, St. Michaels Hospital, Toronto, Ontario, Canada

Michael G. Walsh, MD, Assistant Professor, Epidemiology and Biostatistics, School of Public Health, State University of New York, Downstate, Brooklyn, New York

David Warwick, MD, BM FRCS, FRCS(Orth), Consultant Orthopaedic Surgeon, Reader in Orthopaedic Surgery, University of Southampton, Southampton, United Kingdom

Keith Winters, MD, FRACS, Clinical Fellow, Foot and Ankle Reconstruction, Royal Bournemouth Hospital, Bournemouth, Dorset, United Kingdom

Camilla L. Wong, MD, MHSc, FRCPC, Geriatrician, Assistant Professor, Adjunct Scientist, Division of Geriatrics, University of Toronto, Li Ka Shing Knowledge Institute, St. Michael’s Hospital, Toronto, Ontario, Canada

Joseph D. Zuckerman, MD, Professor and Chairman, Surgeon-in-Chief, Department of Orthopaedic Surgery, NYU Hospital for Joint Diseases, NYU Langone Medical Center, New York, New York
Preface

James P. Waddell, MD, FRCSC
A hip fracture is a life-changing event, not only for the patient but also for their family, friends, and companions. It is increasingly recognized that hip fractures pose not only a personal cost but also a significant societal cost because of the morbidity and mortality that tends to accompany fractures of the proximal femur. For too long the emphasis on hip fracture management has been exclusively surgical. Though no one disputes that a well-performed operation is essential for patient recovery, there are many aspects of hip fracture care that need to be addressed in order to maximize the outcome for the patient. This book attempts to address these other significant issues while providing the most current recommendations regarding the surgical management of fractures of the proximal femur.
In this text we define the scope of the problem and then detail for the reader the most current information regarding the prevention and treatment of osteoporosis. Orthopaedic surgeons have an obligation to learn more about osteoporosis and become actively engaged in the treatment of patients who have this condition and come to their attention as a consequence of a proximal femoral fracture. In addition, we address the appropriate medical assessment of these patients and provide insight into current methods for treatment of the common comorbidities found in these older patients. Radiology, anesthetic techniques, and postoperative pain management are all addressed in separate chapters.
Detailed surgical techniques for femoral neck fractures, intertrochanteric fractures, and subtrochanteric fractures are provided in a comprehensive fashion and are illustrated by diagrams, photographs, and radiographs. The important aspects of postoperative management—including common postoperative complications, delirium, and dementia—are all covered as well, as is a structured rehabilitation program.
I believe that this book is the most comprehensive text currently available for hip fracture management and that, by implementing the recommendations contained herein, outcomes for proximal femoral fractures indeed will be improved.
Foreword

Marc F. Swiontkowski, MD, TRIA Orthopaedic Center, Minneapolis, Minnesota
Dr. Waddell has devoted a career spanning more than 35 years to the study of the best methods of treating hip fractures to improve patient outcome. His personal investigative efforts have covered the full gamut of hip fractures, including femoral neck fractures, intertrochanteric hip fractures, subtrochanteric hip fractures, and associated variants. He has personally analyzed, both in the laboratory and in the clinical setting, optimum biomechanical and clinical methods of stabilizing these fractures or treating them with arthroplasty. This career-long effort now culminates in the comprehensive book Fractures of the Proximal Femur. Dr. Waddell and his 30 authors have provided the orthopaedic community with a comprehensive treatise on the most recent advances in hip fracture epidemiology, preventative strategies, surgical techniques, osteoporosis diagnosis and treatment, and comprehensive rehabilitation strategies. The authors, who are primarily mid career, have significant clinical experience and bring an academic focus to the area. This provides readers with thoroughly researched and referenced chapters on the various types of hip fractures and their optimum treatment.
With the current North American burden of hip fracture of approximately 400,000 per year predicted to escalate to 500,000 per year by 2020, this effort is timely. This book is appropriate for trainees who are attempting to understand the basics of these principles and the experienced community surgeons who are in the trenches and managing these fractures on a daily basis. The balanced approach is to be commended because it provides the reader with a comprehensive understanding of the mechanisms of injury and the pathology of frailty, as well as optimum methods of osteoporosis diagnosis and treatment following hip fracture and ideal rehabilitative strategies. Clearly, hip fracture most often occurs in the setting of aging with diminishing strength and balance and deteriorating bone quality. It is important for the orthopaedic surgeon to focus as much on these issues as on the optimization of surgical treatment. This book is a welcome contribution to any orthopaedic library, will be widely read and cited, and will be a lasting tribute to Dr. Waddell’s devotion to improving patient care for individuals with hip fracture.
Table of Contents
Instructions for online access
Front matter
Copyright
Contributors
Preface
Foreword
Section I: Introduction
Chapter 1: Epidemiology/Population Studies: Scope of the Problem
Section II: Preoperative Assessment of the Hip Fracture Patient
Chapter 2: Skeletal Assessment of Fractures of the Proximal Femur
Chapter 3: General Assessment and Optimization for Surgery
Section III: Anesthesia and Pain Management
Chapter 4: Regional versus General Anesthesia for Fractures of the Proximal Femur
Chapter 5: Improving Pain Management and Patient Outcomes Associated with Proximal Femur Fractures
Section IV: Surgery
Chapter 6: Femoral Neck Fractures: Reduction and Fixation
Chapter 7: Femoral Neck Fractures: Arthroplasty
Chapter 8: Combined Fractures of the Hip and Femoral Shaft
Chapter 9: Femoral Neck Fractures: Treatment of Nonunion
Section V: Intertrochanteric Fractures
Chapter 10: Trochanteric Fractures: Sliding Hip Screw
Chapter 11: Trochanteric Fractures: Intramedullary Devices
Chapter 12: Complications of Trochanteric Fractures
Section VI: Subtrochanteric Fractures
Chapter 13: Subtrochanteric Fractures: Intramedullary Fixation
Chapter 14: Subtrochanteric Fractures: Plate Fixation
Section VII: Postoperative Management
Chapter 15: Deep Vein Thrombosis and Thromboembolism: Prevention and Treatment in Hip Fracture Patients
Chapter 16: Investigation and Management of Postoperative Delirium
Chapter 17: Rehabilitation: Improving Outcomes for Patients Following Fractures of the Proximal Femur
Chapter 18: Preventing the Second Hip Fracture: Addressing Osteoporosis in Hip Fracture Patients
Section VIII: Analysis
Chapter 19: Best Surgical Practices
Chapter 20: Best Rehabilitation Practices
Index
Section I
Introduction
1 Epidemiology/Population Studies
Scope of the Problem

Michael G. Walsh, Joseph D. Zuckerman

Frailty 3
Falls and Fractures 5
After the Fracture 7
Summary 10
Hip fracture represents a tremendous burden on the health care system and public health in general. More than 320,000 people were admitted to hospitals for hip fracture in 2004 in the United States. 1 In 1996, the Centers for Disease Control and Prevention estimated the annual cost of hip fracture to be $2.9 billion. 2 Today, by some estimates that include all direct and indirect costs, it is as high as $12 billion. 3 Even more strikingly, in 1990 it was projected that by 2040 there will be between 530,000 and 840,000 incident cases of hip fracture per year in the United States. 4 From an economic perspective, the cost of hip fracture is tremendous. The morbidity and mortality secondary to hip fracture are equally astounding. Roughly 20% of patients who have hip fracture, or 1 in 5, will die in the year following the fracture, 5 and most of these patients will die in the first months of recovery. 6 Disability increases substantially following hip fracture and is such that the attendant musculoskeletal dysfunction puts the patient at even higher risk for a second fracture or multiple fractures.
To understand the scope of hip fracture outcomes, it is necessary to begin with an understanding of the precursors to the fracture itself. A risk profile is built as an amalgam of physical structure and function and the patient’s environment. This profile encompasses both a syndromic and an event, or outcome, framework, which will ultimately map the individual through the states of frailty and falling to fracture and fracture outcomes sequelae.

Frailty
Frailty represents a syndrome and therefore is recognized as a cluster of symptoms. 7 The syndrome is expressed as diminished physiologic reserve, which is characterized by gait and balance abnormality, weight loss, muscle weakness, loss of energy, and diminished physical activity. 7 - 10 Frailty is a serious public health burden because the syndrome is associated with increased risk of falls, low-velocity fractures, significant disability, and mortality. 11 Indeed, these sequelae often follow this course directly as a chain reaction. Moreover, the syndrome components are generally highly correlated and interactive. For example, physical inactivity leads to increased muscle weakness and diminished gait performance, which in turn make physical activity, ambulation in particular, more difficult. This aggregation of risk through cumulative causal pathways hastens the progression of frailty and leads to more substantive disability, which may be directly related to, or entirely independent of, a traumatic event (e.g., hip fracture).
Central to a conceptual framework for frailty, and by extension hip fracture outcomes, is physiologic reserve. The extent to which one can recover following physical insult or stress is an indication of one’s physiologic reserve and is mediated by aging, physical activity, comorbidity, affect, and cognitive functioning. Individual reserve declines naturally with age, but aging alone is not sufficient for pathologically depleted physiologic reserve. Therefore, frailty is essentially an inability to (1) respond to environmental challenge and (2) recover from injury or disease. As such, because it is characterized by degraded physiologic reserve, frailty not only increases risk of fracture by increasing risk for falling and response to falls, but also increases the likelihood of poor fracture outcomes because of the body’s inability to respond robustly to the traumatic insult. The frail patient who has had a hip fracture then is caught in a vicious cycle of diminished function and poor adaptive response that is not easily mitigated by postoperative rehabilitation either in the hospital or at home. As such, it is critical to assess the patient’s whole medical history, physical functioning, and cognitive status as they existed before the fracture.
Consensus on the clinical designation of frailty has proven difficult, particularly because many clinicians consider frailty and disability synonymous. This viewpoint misses the relevance of preclinical frailty for the development of subsequent morbidity and disability and in turn causes the opportunity for early preventive intervention to be lost. For example, in the context of musculoskeletal dysfunction and hip fracture in particular, gait has been closely associated with frailty in clinical practice. Gait is defined as the pattern of movement during walking and is generally a key component to the frailty complex. The importance of walking to the overall maintenance of homeostasis cannot be overstated. Normal musculo- skeletal, cardiopulmonary, and neurologic functioning are mediated in no small part by the mechanics and chemistry of walking. Moreover, the components of gait strongly influence the mechanics of walking. These components are gait speed, walking cadence (the number of steps walked over a given time period), and stride length. The degeneration in gait speed associated with normal aging appears to result from a decrease in stride length rather than a reduction in cadence. 12 This finding is important because diminished gait speed can be improved in aging individuals with proper physical conditioning.
The Frailty Task Force of the American Geriatric Society proposed a list of criteria to be used in classifying frailty that is now accepted as a working definition for clinical practice. 7 According to this definition, the frailty syndrome is defined by three or more of the following symptoms: (1) unintentional weight loss (4–5 kg in year); (2) self-reported exhaustion; (3) weakness (grip strength <20% in the dominant hand); (4) slow walking speed (<20% for time to walk 15 feet); and (5) low physical activity (<20% for caloric expenditure). 7 Important clinical manifestations of the frailty syndrome include, but are not limited to, gait and balance deficits, sarcopenia, osteopenia and osteoporosis, diminished maximum oxygen consumption (V o 2 max), and potentially elevated or hypertensive blood pressure. Most of these disorders lie directly on the causal pathway to hip fracture and poor outcomes following fracture. Because the inability to respond to stress or physical insult typifies frailty, the frail patient with a hip fracture begins to recover from a baseline that is already in deficit, which retards the body’s adaptive response during convalescence. Consequently, frailty sets the stage not only for the hip fracture itself but also for the inability to recover from that fracture.
Lewis Lipsitz further developed the concept of frailty as a lack of complexity in dynamic systems that leads directly to a loss of what he called “reactive tuning.” 13 Complexity underlies adaptive systems. It is what allows a system to adapt to the events that stress the system. Complexity allows for versatility and provides robustness in the presence of environmental challenge ( Fig. 1-1 ).

Figure 1-1 The physiologic basis of frailty. Multiple interacting physiologic inputs (top) produce highly irregular, complex dynamics (middle) , which impart a high level of functionality (bottom) on an organism. As the inputs and their connections degrade with age, the output signal becomes more regular and less complex, and the result is functional decline. Ultimately, with continued loss of physiologic complexity, function may fall to the critical level below which an organism can no longer adapt to stress (the frailty threshold).
(From Lipsitz LA. Dynamics of stability: The physiologic basis of functional health and frailty. J Gerontol A Biol Sci Med Sci 2002; 57 [3]:B115-25.)
For example, the autonomic nervous system, by way of sympathetic and parasympathetic activity, is responsible for the beat-to-beat variability in heart rate and blood pressure. Endocrine and temperature cues regulate heart rate and blood pressure on scales of minutes to hours, and circadian rhythms regulate across days. Although there may be large variability within any level of internal regulation, the patterning of heart rate and blood pressure is similar across these times scales, a characteristic known as self-similarity. Self-similarity is a key component to the fractal dimensions of complex systems and indeed is largely responsible for the robustness of complex systems. 13 This is why they are adaptive, and this adaptiveness maintains equilibrium. For example, loss of heart rate variability has been recognized as an important trigger for arrhythmia and tachycardia in heart disease and is a common characteristic of aging. 13 More precisely, the system’s complexity allows it to maintain a steady state by myriad self-similar processes. Whereas cardiovascular fitness is an important component of frailty, the adaptation of complex systems is also relevant to the musculoskeletal components of frailty. Specifically, the loss of trabecular bone architecture represents a breakdown of the architectural scale (i.e., a self-similar scale), which directly contributes to bone strength. Stride length, considered one of the most important aspects of gait that can lead to falls, becomes less variable over time. It thus represents a less complex system and therefore is less responsive to environmental or physical challenges.
Center of pressure (COP) is also greatly affected by loss of complexity. COP and posture are strongly related to balance and stability. However, to produce stability, COP requires ongoing displacements (sway). Thus, as greater complexity is introduced into the system, greater stability will result from the system’s need to adapt continuously. All the foregoing examples highlight reactive tuning in complex systems and identify clear pathways to frailty and its consequences when the tuning fails. 13 In other words, we can think of complexity in a system as an ongoing process of challenge or stimulation.

Falls and Fractures
In 1989, Steven Cummings and Michael Nevitt, two prominent researchers in frailty and fracture, wrote a hypothesis article on the causes of hip fractures. 14 This hypothesis mapped falling onto fracture and essentially detailed the causal association between two distinct but strongly associated clinical events. These researchers outlined four necessary conditions that must be present for the hip to fracture on falling. First, the fall must be oriented to land on or near the hip. Second, protective responses must be inadequate to reduce the energy of the fall below a critical threshold for fracture. Third, the soft tissue surrounding the joint must be inadequate to absorb enough of the fall’s energy to prevent the fracture. Fourth, bone strength must be insufficient to resist the residual energy transferred to the hip during the fall ( Fig. 1-2 ). 14

Figure 1-2 Defenses against hip fracture that must fail in order for a fall to result in a hip fracture. ADLs, activities of daily living.
(From Cummings SR, Nevitt MC. A hypothesis: the causes of hip fractures. J Gerontol 1989; 44 [4]:M107-11.)
Before this hypothesis was proposed, conventional thought in hip fracture prevention directed practice to focus primarily on the integrity of bone. As a result, interventions often took the reductionist approach of trying to improve bone mineral density with calcium supplementation. By elucidating a theoretical framework for hip fracture risk that was more systemic, Cummings and Nevitt were able to ground hip fracture in a continuum of declination associated with frailty. Orientation of a fall, for example, is highly dependent on forward momentum or, more specifically, on gait speed during walking. Slower gait speed or shorter stride length, therefore, is more likely to cause an individual to fall down rather than forward while walking. Muscle strength is also directly relevant in fall orientation during transfer motion, and balance, with its associated corrective posturing (reactive tuning), is relevant for falls and their downward orientation when there need not be any movement at all. Poor protective responses include slowed reaction times and decreased muscle strength, both of which may lead to an increased likelihood of falls and diminished capacity to recover from the fall as well as a redirection of the forces involved to obviate a hip fracture. In addition, age-related comorbidity (e.g., distal polyneuropathy, dementia, syncope) can easily reduce responsiveness to one’s environment and can thus inhibit protective responses. 14 Soft tissue, which reduces the energy transferred to the bone on impact, is very important for absorbing the energy of a fall. 14 Weight loss, which can include loss of both fat and lean muscle mass, is a nontrivial component of frailty and often attends the aging process for many individuals. These soft tissues are invaluable as shock absorbers. Their loss removes an individual’s last line of defense in a fall. Moreover, a frail person is likely to have diminished reactive responses to falls, as described earlier, and will hit the ground in an unfavorable orientation with no extra padding to protect from fracture. Finally, the last associative link between falls and fractures outlined by Cummings and Nevitt is the composition of the bone itself. Bone’s ability to endure insult is a composite of mineral content (bone mineral density) and bone architecture (number of trabeculae and width and diameter of cortical bone). These aspects of bone strength are a function of hormonal regulation of bone turnover, nutrition, and mechanical loading by the musculature and overall body mass. Importantly, all these factors are strongly associated with aging. Moreover, frailty is characterized by weakened bone precisely because of hormone dysregulation, undernutrition, and diminished loading of bone resulting from weight loss, muscle weakness, and functional dependence. 14
Inertia is a prominent theme in our discussion of frailty and falls. Indeed it is central not only to the understanding of hip fracture risk, but also to its outcomes, as described in the next section. There is a strong body of evidence for the role played by activity in hip fracture risk. In the 1980s, Boyce and Vessey conducted a study on all femoral neck fractures in patients admitted to all hospitals in the city of Oxford in the United Kingdom. 15 This study is significant because (1) it was population-based and (2) it was composed of a relatively healthy and mobile group of patients because 139 of 333 of these patients passed the cognitive and functional screening test. As such, although we would expect that an activity effect in this group would be attenuated toward the null because the cases would be more similar to controls, the investigators found a strong, significant association between physical inactivity and risk for hip fracture. 15
Another population-based study was conducted in the United Kingdom 5 years later in the borough of Newcastle. 16 This study identified a similar number of hip fractures in the municipality ( N = 312), although 65% of patients passed the mental screening examination for this study (197 of the 303 eligible subjects). The results showed that patients who did no walking each day were three and a half times more likely to fracture their hip even after adjusting for body mass index (BMI), smoking, and dependence in activities of daily living (ADLs) (odds ratio [OR] = 3.4; 95% confidence interval [95% CI], 1.7 to 6.8). 16 The Longitudinal Study of Aging, a population-based study in the United States that was part of the National Health Interview Survey, identified 334 incident fractures among the 7153 eligible community participants. 17 This important study identified a history of previous falls in the past year (OR = 1.3; 95% CI, 1.04 to 1.76), lack of exercise (OR = 1.4; 95% CI, 1.13 to 1.84), social engagement (OR = 1.4; 95% CI,1.11 to 1.78), and hospitalization in the previous year (OR = 1.4; 95% CI, 1.12 to 1.91) as predictors of hip fracture, all independent of age, gender, race, and BMI, which were also strong predictors of hip fracture ( Table 1-1 ). 17

Table 1-1 Cox Proportional Hazards Analysis of Risk Factors Associated with a First Fracture ( N = 7153)
The well-established population-based National Health and Nutrition Examination Survey (NHANES) I Epidemiologic Follow-up study examined risk factors for hip fracture across a representative sample in the United States. The investigators followed 3595 women between the ages of 40 and 77 years for an average of 10 years and recorded 84 incident cases of hip fracture. 18 Study participants who reported little leisure time physical activity (compared with those who reported a lot) were more than twice as likely to fracture their hip even after controlling for age, BMI, smoking, and menopausal status, all of which were, again, significant predictors of hip fracture. 18
The Copenhagen Center for Prospective Population Studies is an aggregate of 3 population-based cohort studies that compiled follow-up data on 15,498 individuals. During follow-up, the Center documented 688 incident hip fractures in women and 433 incident hip fractures in men. 19 The investigators showed that women who participated in moderate leisure time physical activity for either 4 hours or more per week or 2 to 4 hours per week were 35% less likely to experience hip fracture than were sedentary women even after controlling for age, smoking, alcohol use, BMI, level of education, history of chronic disease, and physical activity at work. 19 Consistent with previous studies, these controlled confounding variables were also predictive of hip fracture. A similar pattern emerged for men; however, the adjusted relationship was attenuated and no longer significant (OR for ≥4 hours per week = 0.73; 95% CI, 0.43 to 1.24; OR for 2 to 4 hours per week = 0.69; 95% CI, 0.42 to 1.14). 19 This study remains one of the largest population-based investigations ever undertaken and largely confirms the evidence for physical activity, BMI, sex, and hip fracture risk that has been documented since the 1980s in clinical and smaller-scale population research studies.

After the Fracture
One of the earliest studies to examine both mortality and functional recovery following hip fracture was conducted by Miller in 1978. 20 Miller followed 360 patients with hip fracture for 1 year and found that 27% had died and that only 51% of the survivors had returned to their prefracture ambulatory capacity. The study further found that increasing age, cognitive dysfunction, and male sex were significantly associated with increased mortality and poor ambulation. 20 This study was followed by a large body of evidence demonstrating the high incidence of mortality and functional dependence following hip fracture. 5, 21 - 26
One extremely valuable study of in-hospital mortality was conducted by a team from Johns Hopkins University in Baltimore and identified all Maryland hospital discharges from 1979 through 1988. The investigators looked at all individuals at least 65 years of age who had had a hip fracture as the principal diagnosis according to the International Classification of Diseases, Ninth Revision . 6 These investigators identified age, gender, and comorbidity as the biggest contributors to mortality. Each year increase in age was associated with a 4% increase in in-hospital mortality, whereas men were 60% more likely to die before discharge. 6 Comorbidity was also very strongly associated with early death. Patients with three or more medical diagnoses were three and a half times more likely to die (OR = 3.5; 95% CI, 2.8 to 4.4), whereas those with two medical diagnoses were more than twice as likely (OR = 2.3; 95% CI, 2.0 to 2.7) to die before discharge. Even the presence of a single comorbid condition increased the risk of in-hospital mortality by 50% (OR = 1.5; 95% CI, 1.4 to 1.8). 6
Around this same period, a report from the Established Populations for Epidemiologic Studies of the Elderly (EPESE) also examined the risk of mortality, as well as institutionalization following hip fracture. The investigators found that the presence of two or more comorbid conditions (OR = 9.8; 95% CI, 2.0 to 48.1), femoral neck fracture (OR = 9.1; 95% CI, 1.6 to 51.0), poor cognitive performance (OR = 6.9; 95% CI, 1.1 to 44.2), and number of complications (OR = 2.4; 95% CI, 1.4 to 4.2, for each additional complication occurrence) significantly and independently predicted mortality. 27
Hip fracture substantially exacerbates the normal functional decline associated with aging. Jay Magaziner et al compared the participants of the Baltimore Hip Studies and the EPESE with respect to functional decline. 28 ADLs served as the functional measure of comparison between these two cohorts. These investigators focused on three ADL components to maximize comparability between the two studies. The components were walking, transferring, and grooming, and they were graded according to whether the individual could perform the activity independently, with help, or not at all. 28 The patients with hip fracture were twice as likely to be dependent in walking at both 12 months (50% versus 21% to 22%, respectively) and 24 months (50% versus 25% to 29%, respectively) despite similar levels of dependence in both groups at baseline.
Mobility after the fracture is as important in the recovery of function and the prevention of mortality as it is in the prevention of falls and hip fracture. Siu et al from four hospitals in the northeastern United States (Mount Sinai School of Medicine in New York, The Bronx New York Harbor Veterans Affairs Medical Center, New York University [NYU] Hospital for Joint Diseases, and Dartmouth Medical School in New Hampshire) showed the important effects of early ambulation on the function and mortality experience up to 6 months following surgery. 29 For every single day increase in postoperative immobility, patients were 75% more likely to die by 6 months of follow-up. With respect to ambulatory function, each extra day of immobility following surgery was associated with a 0.70 decrease in the Functional Independence Measure (FIM) locomotion score at 2 months and a 0.44 decrease at 6 months, although the latter score was not statistically significant. 29 Moreover, when patients were stratified on preoperative mobility status, the differences were even more pronounced. Those patients who required personal assistance or supervision during locomotion were three times more likely to die by 6 months if they were in the top 90th percentile of the number of days of postoperative immobility compared with the bottom 10th percentile ( P = .004). Twenty-eight percent of patients in the 90th percentile died by 6 months compared with 17.7% in the 50th and 11.3% in the 10th percentiles, respectively. Similar differences were not observed for patients who were independently mobile at baseline; these patients had 1.6%, 2.1%, and 2.8% mortality in the 90th, 50th, and 10th percentiles of postoperative immobility, respectively, by 6 months. 29
In an earlier study, Siu et al showed that a composite of prefracture locomotion, the Acute Physiology and Chronic Health Evaluation (APACHE) score, and professional home assistance before fracture were all associated with both mortality and occurrence of adverse outcomes by 6-month follow-up ( Table 1-2 ). 30 Additionally, these investigators showed that locomotion at 6 months was significantly predicted by prefracture locomotion, age, residence in a nursing home, and assisted living ( Table 1-3 ). 30

Table 1-2 Hip Fracture: Predictors of 6-Month Mortality and Adverse Outcome (Death or Needing Total Assistance to Ambulate) Using Logistic Regression*
Table 1-3 Hip Fracture: Predictors of Locomotion at 6 Months ( N = 45) Using Multiple Linear Regression *   Locomotion Risk Factor Parameter Estimate P Value Intercept 7.573 <.001 Prefracture locomotion 0.498 <.001 Modified RAND comorbidity score −0.080 .18 Modified APACHE score −0.090 .23 Age −0.044 .02 Male sex −0.371 .36 Nursing home residence −1.406 .02 Dementia −0.739 .09 Paid helper at home before fracture −0.602 .10
APACHE, Acute Physiology and Chronic Health Evaluation.
* Male sex, nursing home residence, dementia, and paid helper at home before fracture are binary (yes/no) variables; the other variables are measured on a continuum and the parameter estimate refers to the impact of a unit change.
Adapted from Hannan EL, Magaziner J, Wang JJ, Eastwood EA, Silberzweig SB, Gilbert M, et al. Mortality and locomotion 6 months after hospitalization for hip fracture: risk factors and risk-adjusted hospital outcomes. JAMA 2001; 285 (21):2736-42.
These studies indicate the primary importance of preoperative and early postoperative mobility for positive outcomes, particularly for independent function and decreased mortality. The work also highlights the critical role played by cognitive ability, comorbidity, and level of independence in ADLs, all of which were significantly associated with mortality and adverse outcomes in the foregoing studies and the last two of which were associated with locomotion at 6-month follow-up. 29, 30
Another collaborative effort, known as the Three Cohort Study, which again included the NYU Hospital for Joint Diseases and Mount Sinai patient populations while adding patients from the Baltimore Hip Studies population, identified risk clusters based on baseline prefracture characteristics and 6-month postfracture outcomes. Seven distinct clusters were classified according to sex, race, age, comorbidity, and ADLs ( Fig. 1-3 ). 31

Figure 1-3 Patient classification decision tree for seven-cluster solution.
(From Penrod JD, Litke A, Hawkes WG, Magaziner J, Koval KJ, Doucette JT, et al. Heterogeneity in hip fracture patients: age, functional status, and comorbidity. J Am Geriatr Soc 2007; 55 : 407-13.)
These clusters aggregated into two broad groups defined by age, with the young-old groups less than 85 years old and old-old groups 85 years old and older. The two cluster groups further aggregated patients into clusters defined by functional capacity, with increasing dependence and decreasing mobility identifying poorer functional outcomes at 6 months. 31 There was a further level of cluster stratification among the old-old clusters with the greatest functional dependence. This final stratum was defined by the presence of dementia. The cluster analysis results portray a very useful representation of risk clustering associated with hip fracture and its outcomes by providing visual mapping of outcomes mediation by mobility, age, and, for the very old and disabled, cognitive ability. Mobility and age clearly designate subgroups of patients who are likely to recover poorly. Outcomes appear to proceed along a continuum of functional, and to a lesser extent, cognitive capacity that determines the process of aging, the risk of falling and fracturing the hip, and ultimately the degree of recovery for those who do experience a fracture. Unfortunately, the process that predisposes an individual to hip fracture is the same process that predisposes him or her to poor functional outcomes following the fracture. Therefore, promoting improved function is in many ways similar to preventing fracture because we must employ mobility as a primary intervention to combat frailty.
Data reported by Aharonoff et al further showed that functional independence is an important predictor of mortality in the first year following the fracture. Patients with dependence in ADLs experienced 70% greater mortality in the first year, independent of elderly age (≥85 years old), comorbidity (particularly a history of malignancy), high-risk American Society of Anesthesiologists (ASA) grade, and the presence of any postoperative complications, all of which were also significantly associated with increased 1-year mortality ( Table 1-4 ). 26

Table 1-4 Predictors of 1-Year Mortality After Hip Fracture
In a later report on the foregoing patient population, Paksima et al presented data through 10 years of follow-up. 32 This report again highlighted the importance of prefracture physical function on postfracture mortality. Those patients who were unable to walk outside their home were more than twice as likely to die during follow-up than were patients who had normal walking function (hazard ratio = 2.19; 95% CI, 1.7 to 2.9) even after controlling for age, gender, baseline comorbidity and ASA score, and postoperative complications ( Table 1-5 ). Furthermore, even ambulation with an assistive device was independently associated a significant 28% increase in mortality over follow-up. 32

Table 1-5 Predictors of Mortality (Multivariable Analysis Using Extended Cox Model)

Summary
Gender, old age, body mass, and comorbidity are, as outlined earlier, all important indicators for hip fracture outcomes. Virtually every study examining hip fracture and its outcomes has shown this. The literature supports the critical roles that these factors play in the risk for hip fracture initially and then for mortality and poor functional recovery following the incident fracture. Nevertheless, the overriding theme throughout this chapter is the importance of mobility. Inertia is the enemy of aging. It precipitates functional decline and removes complexity from physiologic systems, thus diminishing responsiveness to environmental challenge. As such, the patient with a hip fracture who has depleted physiologic reserve has a difficult course of recovery. Based on solid evidence from population-based studies, breaking the cycle of inertia and functional decline may be the most important prospect for improving health outcomes after hip fracture. Because frailty appears to be a reversible process, 33 initiating greater mobility has the potential to combat frailty directly and thus promote healthy aging at all points along the continuum of functional decline, falls, fracture, and ultimately recovery.
It is incumbent on the hip fracture rehabilitative team to reintroduce greater complexity into an aging musculoskeletal system by providing challenge and stimulation, even after such a severe injury. The evidence strongly suggests the central role such an approach to remobilization can take in recovering from hip fracture. Indeed, mobility is perhaps the only directly modifiable patient risk factor for poor hip fracture outcomes. Ultimately, the focus must be to combat frailty whether we are trying to prevent fracture or trying to promote functional recovery following it. At its core, this means that we assume a commitment to healthy aging regardless of the orthopaedic context.

References

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2 Baron J.A., Barrett J., Berger M. Incidence and costs to Medicare of fractures among Medicare beneficiaries aged greater than or equal to 65 years—United States, July 1991–June 1992. MMWR Morb Mortal Wkly Rep . 1996;45(41):877-883.
3 Burge R., Dawson-Hughes B., Solomon D.H., Wong J.B., King A., Tosteson A. Incidence and economic burden of osteoporosis-related fractures in the United States, 2005–2025. J Bone Miner Res . 2007;22(3):465-475.
4 Schneider E.L., Guralnik J.M. The aging of America: impact on health care costs. JAMA . 1990;263(17):2335-2340.
5 Leibson C.L., Tosteson A., Gabriel S.E., Ransom J.E., Melton L.J.III. Mortality, disability, and nursing home use for persons with hip fracture: a population-based study. J Am Geriatr Soc . 2002;50(10):1644-1650.
6 Myers A.H., Robinson E.G., Van Natta M.L., Michelson J.D., Collins K., Baker S.P. Hip fractures among the elderly: factors associated with in-hospital mortality. Am J Epidemiol . 1991;134(10):1128-1137.
7 Fried L.P., Tangen C.M., Walston J., Newman A.B., Hirsch C., Gottdiener J., et al. Frailty in older adults: evidence for a phenotype. J Gerontol . 2001;56A(3):M146-M156.
8 Rockwood K., Stadnyk K., MacKnight C., McDowell I., Hebert R., Hogan D.B. A brief clinical instrument to classify frailty in elderly people. Lancet . 1999;353:205-206.
9 Brown M., Sinacore D.R., Binder E.F., Kohrt W.M. Physical performance measures for the identification of mild to moderate frailty. J Gerontol . 2000;55A(6):M350-M355.
10 Runge M., Hunter G. Determinants of musculoskeletal frailty and the risk of falls in old age. J Musculoskelet Neuronal Interact . 2006;6(2):167-173.
11 Ensrud K.E., Ewing S.K., Taylor B.C., Fink H.A., Stone K.L., Cauley J.A., et al. Frailty and risk of falls, fracture, and mortality in older women: the study of osteoporotic fractures. J Gerontol . 2007;62(7):744-751.
12 Rubino F.A. Gait disorders. Neurologist . 2002;8(4):254-262.
13 Lipsitz L.A. Dynamics of stability: The physiologic basis of functional health and frailty. J Gerontol A Biol Sci Med Sci . 2002;57(3):B115-B125.
14 Cummings S.R., Nevitt M.C. A hypothesis: the causes of hip fractures. J Gerontol . 1989;44(4):M107-M111.
15 Boyce W.J., Vessey M.P. Habitual physical inertia and other factors in relation to risk of fracture of the proximal femur. Age Ageing . 1988;17:319-327.
16 Coupland C., Wood D., Cooper C. Physical inactivity is an independent risk factor for hip fracture in the elderly. J Epidemiol Community Health . 1993;47:441-443.
17 Young Y., Myers A.H., Provenzano G. Factors associated with time to first hip fracture. J Aging Health . 2001;13(4):511-526.
18 Farmer M.E., Harris T., Madans J.H., Wallace R.B., Coroni-Huntley J., White L.R. Anthropometric indicators and hip fracture: the NHANES I epidemiologic follow-up study. J Am Geriatr Soc . 1989;37(1):9-16.
19 Hoidrup S., Sorensen T.I.A., Stroger U., Lauritzen J.B., Schroll M., Gronbaek M. Leisure-time physical activity levels and changes in relation to risk of hip fracture in men and women. Am J Epidemiol . 2001;154(1):60-67.
20 Miller W. Survival and ambulation following hip fracture. J Bone Joint Surg Am . 1978;60:930-934.
21 Keene J.S., Andersen C.A. Hip fractures in the elderly: discharge predictions with a functional rating scale. JAMA . 1982;248:564-567.
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23 Kenzora J.E., McCarthy R.E., Lowell J.D., Sledge C.B. Hip fracture mortality, relation to age, treatment, preoperative illness, time to surgery and complications. Clin Orthop . 1984;186:45-56.
24 Magaziner J., Simonsick E.M., Kashner T.M. Survival experience of aged hip fracture patients. Am J Public Health . 1989;79:274-278.
25 Marottoli R.A., Berkman L.F., Cooney L.M. Decline in physical function following hip fracture. J Am Geriatr Soc . 1992;40(9):861-866.
26 Aharonoff G.B., Koval K.J., Skovron L. Hip fractures in the elderly: predictors of one year mortality. J Orthop Trauma . 1997;11(3):162-165.
27 Marottoli R.A., Berkman L.F., Leo-Summers L., Cooney L.M. Predictors of mortality and institutionalization after hip fracture: the New Haven EPESE Cohort. Am J Public Health . 1994;84:1807-1812.
28 Magaziner J., Fredman L., Hawkes W., Hebel J.R., Zimmerman S., Orwig D.L., et al. Changes in functional status attributable to hip fracture: a comparison of hip fracture patients to community-dwelling age. Am J Epidemiol . 2003;157:1023-1031.
29 Siu A.L., Penrod P.D., Boockvar K.S., Koval K., Strauss E., Morrison S. Early ambulation after hip fracture: effects on function and mortality. Arch Intern Med . 2006;166:766-771.
30 Hannan E.L., Magaziner J., Wang J.J., Eastwood E.A., Silberzweig S.B., Gilbert M., et al. Mortality and locomotion 6 months after hospitalization for hip fracture: risk factors and risk-adjusted hospital outcomes. JAMA . 2001;285(21):2736-2742.
31 Penrod J.D., Litke A., Hawkes W.G., Magaziner J., Koval K.J., Doucette J.T., et al. Heterogeneity in hip fracture patients: age, functional status, and comorbidity. J Am Geriatr Soc . 2007;55:407-413.
32 Paksima N., Koval K.J., Aharanoff M.G., Walsh M., Kubiak E.N., Zuckerman J.D., et al. Predictors of mortality after hip fracture: a 10 year prospective study. Bull Hosp Jt Dis . 2008;66(2):111-117.
33 Lang P.O., Michel J.P., Zekry D. Frailty syndrome: a transitional state in a dynamic process. Gerontology . 2009;55(5):539-549. doi:10.1159/ 000211949
Section II
Preoperative Assessment of the Hip Fracture Patient
2 Skeletal Assessment of Fractures of the Proximal Femur

Dawn H. Pearce

Radiologic Evaluation 15
Computed Tomography 15
Magnetic Resonance Imaging 18
Bone Scan 19
Special Types of Fractures 20
Avulsion Fractures 20
Pathologic Fractures 20
Stress Fractures 21
Summary 23
Evaluation of the painful hip is a daily occurrence in most hospital settings. A painful hip is most commonly seen in the elderly osteoporotic population. Plain film radiographs are the initial study of choice to evaluate these patients.
Although most proximal femur fractures are easily detected on routine x-ray studies, nondisplaced fractures of the hip are a reality and a challenge for imagers and surgeons alike. Radio-occult fractures of the hip are fractures that escape detection on routine x-ray imaging. A high index of suspicion is needed for patients in excessive pain or those refusing to bear weight. When the clinical situation does not correspond to a “negative hip x-ray,” these patients warrant further investigation. Imaging choices include computed tomography (CT), magnetic resonance imaging (MRI), and bone scan. Bone tomograms are of historical interest but are no longer performed. Rapid diagnosis and early treatment of occult fractures are in the patient’s best interest because this approach reduces the chance that a nondisplaced fracture will displace, a situation that requires more invasive management and increases morbidity. 1

Radiologic Evaluation
The routine radiographs used to evaluate hip fractures include anteroposterior (AP) and lateral views of the hip ( Fig. 2-1 ). Frog leg views are not recommended in an acute hip fracture for fear of dislocation or displacement of fragments. An AP view of the pelvis is also recommended because so many elderly patients with hip pain and inability to bear weight have pubic rami fractures, which may be more visible on the pelvic x-ray film. In suspected cases of avascular necrosis (AVN) of the hip, a frog leg view can be helpful to evaluate for subchondral fracture of the femoral head ( Fig. 2-2 ).

Figure 2-1 A, Anteroposterior radiograph of the left hip shows an intertrochanteric fracture. B, Lateral radiograph of the left hip shows anterior displacement of the femoral shaft relative to the neck. The ischial tuberosity is an excellent anatomic landmark that is posteriorly located.

Figure 2-2 A, Frog leg radiograph of the hip shows a subchondral radiolucent fracture line referred to as a crescent sign. This indicates a relatively advanced stage of avascular necrosis (AVN). B, Anteroposterior radiograph of another hip with a more advanced stage of AVN, with fracture and depression of the articular surface of the femoral head.
The choice of CT, MRI, or bone scan depends partly on what is available to patients. For example, some centers do not offer nuclear medicine imaging at night or on weekends. In addition, some MRI technologists are available only on an on-call basis after hours, and this service is generally reserved for dire emergencies such as spinal cord compression. Some institutions have a 24-hour in-house CT technologist, so it is much easier for an emergency department patient to obtain a CT scan than an MRI. Hence, CT is often the next imaging test used to follow up on an equivocal or negative hip x-ray study at some institutions.

Computed Tomography
CT is a modality that is often readily available in the hospital setting, especially after hours. The CT imaging protocol has changed significantly in the last few years. Thin-cut slices that are 0.6 mm thick have become routine, whereas in the past much thicker slices, such as 3-mm cuts, were used. The older, thick slices had very choppy reformations, which made fracture detection more difficult. Today’s thin slices allow one to obtain beautifully detailed coronal and sagittal reformatted images ( Fig. 2-3 ). Reformatted images, especially in the coronal plane, are recommended and often show a proximal femur hairline fracture more clearly ( Fig. 2-4 ). In theory, the use of only axial imaging may fail to reveal fractures that are parallel to the axial imaging plane. 2

Figure 2-3 A, Anteroposterior radiograph of the right hip shows an intertrochanteric fracture. B, A computed tomography (CT) scan was performed to evaluate for other fractures in this 29-year-old male cyclist who fell off his bike. Coronal reformatted CT image shows an impacted intertrochanteric fracture. C, Axial CT image in same patient, displayed on soft tissue windows. The fat-fluid level indicates lipohemarthrosis.

Figure 2-4 Coronal reformatted computed tomography image shows a subtle hairline intertrochanteric fracture. The plain film was negative, even in retrospect.
CT can be vital to operative planning in the established proximal femur fracture. This imaging technique allows excellent assessment of intra-articular bone fragments, such as in a patient with a history of hip dislocation 3 ( Figs. 2-5 and 2-6 ). It also shows such fine bony detail that articular collapse can be assessed in cases of AVN.

Figure 2-5 A, Anteroposterior radiograph in a 55-year-old man who fell onto his backyard deck shows anterolateral dislocation of the femoral head. B, Cross-table lateral radiograph of the hip shows anterolateral dislocation of the femoral head. C, Coronal reformatted computed tomography image of the hip performed after reduction shows a large osteochondral impaction injury of the superolateral aspect of the femoral head. The femoral head is located well within the acetabulum, and no intra-articular fracture fragments were found.

Figure 2-6 A, Anteroposterior radiograph taken after reduction of a hip dislocation. A vague lucency is noted in the superolateral femoral head and neck. A tiny linear bone fragment is noted inferior to the femoral head. B, Axial computed tomography image of the same patient performed within 1 hour of A shows an oblique fracture of the femoral head. A small fracture fragment lies at the posterior wall of the acetabulum, and a subtle intra-articular bone fragment was identified.
One study showed MRI to be a more accurate modality than CT scan for early diagnosis of occult hip fractures 4 ( Fig. 2-7 ). The image slice thickness in that study was 3.2 mm, much thicker than what would be used today.

Figure 2-7 A, Axial computed tomography (CT) image of the right hip shows a hairline fracture of the superior aspect of the femoral neck. B, Anteroposterior radiograph in the same patient shows a hairline vertical fracture of the superior femoral neck. A hip fracture was not suspected clinically in this 28-year-old female intravenous drug abuser who gave no history of trauma. The CT scan had been performed to rule out intramuscular abscess.
A CT scan takes approximately 5 minutes to perform, although patient immobility may increase this time because it may take longer to transfer the patient from the hospital stretcher to the CT table. The actual scanning time is approximately 30 seconds; therefore, CT may be preferred in patients who are unable to remain still. CT scan of the pelvis is not degraded by quiet respiratory motion, but it is degraded by patients who cannot keep still for 30 seconds, such as demented elderly patients in extreme pain.

Magnetic Resonance Imaging
MRI is excellent at detecting occult fractures. A study of 15 osteopenic patients with normal plain radiographs and suspected hip fractures were imaged with MRI. Ten of the 15 patients showed a clear fracture on MRI, and these patients then underwent surgery based on the MRI study. The other 5 patients had no fracture noted on MRI and were successfully treated nonoperatively. 5 MRI can also delineate disorders adjacent to fractures, such as infarcts or metastases, and nonsurgical entities such as pubic rami fractures ( Fig. 2-8 ), bursitis, and muscle strain ( Fig. 2-9 ).

Figure 2-8 Coronal T1-weighted magnetic resonance image in a patient with hip pain shows a low signal intensity fracture line in the superior pubic ramus.

Figure 2-9 Axial T2-weighted magnetic resonance imaging scan with fat saturation in an elderly woman who would not bear weight. Note the extensive high signal intensity throughout the adductor muscle group. An inferior pubic ramus fracture is also noted, and it was better seen on the T1-weighted image (not shown).
The sequences of a routine hip MRI scan vary from institution to institution. Coronal T1-weighted imaging and coronal T2-weighted imaging with fat saturation are the cornerstone sequences used to rule out hip fracture ( Figs. 2-10 and 2-11 ). Coronal short inversion time inversion-recovery (STIR) images may be used instead of T2-weighted images with fat saturation. A routine hip MRI takes approximately 30 minutes to perform. If only the bare minimum coronal T1-weighted and coronal T2-weighted fat saturation images are performed, scanning time is reduced to just less than 15 minutes. Depending on the patient’s condition, 15 minutes of lying supine and perfectly still can be difficult. Motion artifact is the enemy of MRI, and it can render a test nondiagnostic. Cardiac pacemakers are a contraindication to MRI, and hence some patients are excluded from this test.

Figure 2-10 A, Coronal T1-weighted magnetic resonance imaging (MRI) scan shows a low signal intensity fracture line across the femoral neck. B, The corresponding coronal T2-weighted MRI scan with fat saturation shows the fracture line less distinctly because of the surrounding bone marrow edema in the femoral neck.

Figure 2-11 A, Coronal T1-weighted magnetic resonance imaging (MRI) scan shows thickening of the medial femoral cortex, but no fracture line. B, Corresponding T2-weighted MRI scan with fat saturation shows an abnormally high T2 signal intensity resulting from bone marrow edema. A diagnosis of stress reaction was made because no stress fracture line could be identified.
One study of 70 patients with possible hip fracture but negative x-ray results showed that in those patients who underwent MRI to evaluate for possible radiographically occult hip fracture, 80% had a bone or soft tissue abnormality. Occult hip fracture was seen in 37%, and occult pelvic fracture was diagnosed in 23%. Soft tissue abnormalities were noted in 74% of patients. When a proximal femoral fracture was not present, MRI showed a 27% frequency of occult pelvic fracture and a 50% frequency of bone or soft tissue injury. 6

Bone Scan
Bone scintigraphy is a sensitive method to detect bone abnormalities. It has been used to detect radio-occult hip fractures, especially in elderly patients with acute hip pain. A bone scan takes approximately 3½ hours to perform.
Although bone scan is highly sensitive, it is often nonspecific, and false-negative and false-positive results do occur. Results of a bone scan may be negative immediately after an injury or fall, especially in the elderly. 7 In a study of the appearance of bone scans following fracture, it was reported that 95% of patients less than 65 years of age had an abnormal bone scan by 24 hours after injury, and 95% of all patients had an abnormal bone scan by 72 hours. By 7 days, 100% of patients less than 65 years old who had fractures had an abnormal bone scan, compared with 98% of patients more than 65 years old. These rare patients who have a fracture but a negative bone scan result are generally elderly osteoporotic patients with slow bone turnover and healing. 8 Some investigators believe that a negative bone scan in a patient who is more than 65 years of age should be repeated 3 days after injury before a definitive “no fracture” decision is made. 5
Bone scans lack spatial resolution, and increased osteoblastic activity may be caused by other pathologic processes besides fracture. 5 A bone scan does not provide the precise anatomic location of a fracture and often necessitates further imaging ( Fig. 2-12 ). One institution reported five cases within a 1-year study in which a false-positive bone scan resulted from a collar or rim of osteophytes around the femoral neck. 2 The implications of a false-positive bone scan can be serious because treatment of hip fractures often requires emergency surgery. The investigators concluded that bone scans obtained for suspected occult hip fracture should be compared with x-ray findings. The presence of osteophytes around the joint should prompt CT or MRI correlation if the bone scan appears positive for fracture of the femoral neck. 2

Figure 2-12 A, Anterior bone scan of the pelvis shows increased uptake in both femoral necks. B, Coronal T1-weighted magnetic resonance image of the same pelvis shows low signal intensity fracture lines across bilateral femoral necks. The patient had a history of local radiation therapy for rectal carcinoma, and a diagnosis of insufficiency fractures was made.
A single study clearly demonstrated a 1-day delay in the diagnosis of occult hip fracture when bone scan was used instead of MRI. The time to diagnosis was 2.24 ± 1.30 days for bone scanning and 0.368 ± 0.597 days for MRI ( P < .0001). 9 This study was conducted at a U.S. center, which may have had better access to MRI scanners. The conclusion was that by shortening the time to diagnosis, MRI prevents unnecessary hospitalizations and delays in definitive treatment. 9

Special Types of Fractures

Avulsion Fractures
Apophyseal avulsion fractures of the greater and lesser trochanters often occur in male adolescents involved in vigorous sports such as running and football, and these injuries generally present as pain. 10 Conversely, in adults, an avulsion of the lesser trochanter is usually the result of a pathologic fracture ( Fig. 2-13 ). A diagnosis of nontraumatic avulsion fracture of the lesser trochanter in an adult should be considered pathologic until proven otherwise. 11 If the patient has not been diagnosed as having a primary neoplasm, further metastatic workup is recommended. 12

Figure 2-13 A, Anteroposterior radiograph shows a slightly displaced fracture of the lesser trochanter. B, Axial computed tomography image in same patient shows diffuse sclerosis involving the entire left lesser trochanter, with a pathologic fracture. C, A bone scan was performed as part of a metastatic workup. Anterior and posterior bone scan images show widespread skeletal metastases. The patient was found to have primary lung carcinoma.

Pathologic Fractures
A pathologic fracture is one in which the bone is disrupted at a site of a preexisting abnormality, most commonly the result of an underlying tumor. The most common tumors associated with pathologic fractures are skeletal metastases. Less common tumors include benign lesions (simple bone cyst, enchondroma, and giant cell tumors) and primary malignant tumors of bone. Large and aggressive lesions are more apt to fracture pathologically than are small, nonaggressive lesions. 13
Often the amount of stress needed to cause a pathologic fracture is less than that needed to fracture a normal bone. Identification of a lesion at risk for fracture is important because the surgeon may prophylactically intervene surgically. Tumor size and extent of cortical destruction are key factors that influence the risk of pathologic fracture. CT scan is superior to routine radiographs to display tumor extent and cortical destruction ( Fig. 2-14 ). MRI is excellent to show tumor extent, but its role in evaluating cortical detail is unknown. 13

Figure 2-14 A, Anteroposterior (AP) radiograph of the hip shows a lytic lesion in the intertrochanteric region, with endosteal scalloping and thinning of the lateral bony cortex. The patient had a history of nephrectomy for renal cell carcinoma 3 years earlier. B, Axial computed tomography image of the hips shows destruction of the anterior cortex in the right femoral neck. The entire cross section of the bone marrow space is replaced by soft tissue tumor. C, Six days later, the patient developed severe right hip pain. AP radiograph of the hip shows an interval pathologic subtrochanteric hip fracture that required intramedullary nail fixation. Intraoperative biopsy showed metastatic renal cell carcinoma.
Determining whether a hip fracture is pathologic can be difficult. It can also be easy, such as in the setting of a large lytic lesion that fractures in a patient with evidence of widespread metastatic disease throughout the pelvis ( Fig. 2-15 ). When a small lytic or sclerotic lesion pathologically fractures, the fracture fragments can obscure the tumor, especially when there are displaced fragments. Cross-sectional imaging may be needed to determine whether a fracture is pathologic.

Figure 2-15 Anteroposterior radiograph of the hip shows a large, lobulated lytic lesion in the intertrochanteric and subtrochanteric regions, with a pathologic fracture of the lesser trochanter. Biopsy revealed multiple myeloma.
Nonpathologic fractures of the hip can sometimes be misleading and appear pathologic. For example, an x-ray film of a hip fracture may show homogeneous increased density of the proximal femoral diaphysis, which has been shown to be related to external rotation of the femoral shaft. One study that used CT scans showed that the misleading appearance resulted from different cortical thickness between the AP and the mediolateral shaft, which becomes accentuated with external rotation of the proximal femur. 14
Sometimes subcapital fractures of the femoral neck in elderly osteoporotic patients have an x-ray appearance of a pathologic fracture because of lucency at the superolateral subcapital region. One study showed that 17% of subcapital hip fractures had this appearance, but only in Garden III and Garden IV fractures. Evaluation of cadaveric specimens showed that the misleading appearance simulating a pathologic fracture was primarily caused by external rotation of the distal fracture fragment and was accentuated by displacement among fracture fragments. 15

Stress Fractures
There are two categories of stress fractures: fatigue and insufficiency. Fatigue fractures are caused by unusual or repeated stress on a normal bone, such as a march fracture in the metatarsal of an army recruit. Insufficiency fractures are caused by normal or physiologic stress placed on an abnormal, weakened bone that has lost bone trabeculae and has decreased elastic resistance. 13 Generally, fatigue fractures are seen in young, healthy athletic patients, and insufficiency fractures are seen in elderly osteoporotic women.
Stress fractures can be occult because they are usually nondisplaced. Runners typically have stress fractures at either the pubic ramus or the medial femoral neck, so it is important to know the expected location of these fractures ( Fig. 2-16 ). Initially, acute stress fractures may be detected as a subtle lucency or sclerosis, or they may be radio-occult. When subacute, stress fractures are better seen, with a lucent line surrounded by sclerosis ( Fig. 2-17 ). 11 When stress fracture is considered in a patient with repetitive trauma who has a normal x-ray study, plain radiographs should be supplemented with a bone scan or MRI scan. MRI can be performed quickly, is cost effective, and is sensitive and specific for the diagnosis of occult fracture. 7

Figure 2-16 A, Anteroposterior radiograph in a 26-year-old female avid jogger shows a small focus of periostitis along the medial aspect of the femoral neck. B, Coronal T2-weighted magnetic resonance imaging (MRI) scan with fat saturation shows an abnormally bright T2 signal intensity within the medial aspect of the distal femoral neck resulting from extensive bone marrow edema. C, Coronal T1-weighted MRI scan shows a small, focal low signal intensity region along the medial femoral neck, in keeping with an early stress fracture. The patient was advised to stop her athletics in order to heal. MRI scan and x-ray studies performed 8 months later showed complete interval resolution of the radiographic findings, including the tiny amount of periostitis along the medial femoral neck.

Figure 2-17 A, Anteroposterior radiograph of the hip in an osteoporotic woman shows an insufficiency fracture in the lateral cortex of the proximal femur. B, Magnified view of A shows a lucent fracture line at a 90-degree angle to the cortex, with cortical thickening and endosteal thickening.
Insufficiency fractures of the femur most commonly occur in the subcapital region and can be seen as a linear subtle band of sclerosis on plain radiographs ( Fig. 2-18 ). MRI is excellent for detecting stress fractures ( Fig. 2-19 ). The T1-weighted images show the fracture line itself. T2-weighted images with fat saturation and STIR images may not show the fracture line because it can be obscured by the surrounding high signal intensity edema. 11

Figure 2-18 Coronal reformatted computed tomography image of the pelvis shows bilateral displaced subcapital insufficiency fractures. Multiple osteoporotic fractures are also seen in the lumbar spine.

Figure 2-19 A, Anteroposterior (AP) radiograph of the hip shows mild periostitis along the lateral cortex of the proximal femur in a 75-year-old woman with chronic myelogenous leukemia who had pain and a limp while walking. B, Anterior bone scan shows increased tracer uptake in the proximal third of the femur. C, Sagittal T1-weighted magnetic resonance imaging (MRI) scan of the femur shows an oblique low signal intensity fracture line extending across the medullary canal. D, Coronal T2-weighted MRI scan with fat saturation shows significant intramedullary abnormal T2 signal intensity resulting from bone marrow edema. Focal cortical thickening is seen, corresponding to the finding on the AP radiograph. A thin slip of periosteal fluid is noted.

Summary
The diagnosis of a hip fracture is generally made by plain radiographs. Unfortunately, some hip fractures are radio-occult and warrant further imaging. MRI is excellent at detecting occult fractures. Ideally, MRI should be the initial imaging modality following routine hip and pelvis radiographs because of its high specificity and the additional clinically important information that MRI can reveal. 7 This information includes the extent of soft tissue injury and the presence of other occult pelvic fractures. Depending on the center and country where you practice, MRI may not be readily available.
MRI can easily confirm or deny the presence of a minimally displaced hip fracture. Coronal T1-weighted images and coronal T2-weighted fat saturation images are the critical sequences needed to make the diagnosis of hip fracture. The T1-weighted images show the fracture line itself. The T2-weighted images with fat saturation show the intramedullary bone marrow edema, but the fracture line is usually less distinct on this sequence.
CT scan has changed in recent years. The slice thickness is now down to 0.6 mm. These thin slices allow excellent coronal reformatted images to be obtained, thus allowing hip fractures to be more easily detected. Fracture extent and displacement are well seen with CT. In the setting of major trauma or recent hip dislocation, CT is the preferred modality because it is a fast study and it shows the presence of intra-articular fracture fragments and associated acetabular fractures.
Isolated nontraumatic avulsion fracture of the lesser trochanter in adults has been recognized as a pathognomonic sign of metastatic disease. 16 CT is an excellent tool to evaluate for cortical destruction and tumor extent in the setting of skeletal metastases. The findings aid the surgeon to make a decision regarding the risk of pathologic fracture and whether to prophylactically intervene surgically. Stress fractures can be difficult to detect because they are usually nondisplaced. MRI is an excellent modality to reveal stress fractures in the proximal femur and pelvis.

References

1 Rizzo P.F., Gould E.S., Lyden J.P., et al. Diagnosis of occult fractures about the hip: magnetic resonance imaging compared with bone-scanning. J Bone Joint Surg Am . 1993;75:395-401.
2 Garcia-Morales F., Seo G.S., Chengazi V., et al. Collar osteophytes: a cause of false positive findings in bone scans for hip fractures. AJR Am J Roentgenol . 2003;181:191-194.
3 Resnick D. Physical injury: extraspinal sites. In: Resnick D., editor. Diagnosis of bone and joint disorders . 4th ed. Philadelphia: Saunders; 2002:2854-2868.
4 Lubovsky O., Liebergall M., Mattan Y., et al. Early diagnosis of occult hip fractures: MRI versus CT scan. Injury . 2005;36:788-792.
5 Haramati N., Staron R.B., Barax C., et al. Magnetic resonance imaging of occult fractures of the proximal femur. Skeletal Radiol . 1994;23:19-22.
6 Gogost G.A., Lizerbram E.K., Crues J.V. MR imaging in evaluation of suspected hip fracture: Frequency of unsuspected bone and soft-tissue injury. Radiology . 1995;197:263-267.
7 Newberg A.H., Newman J.S. Imaging of a painful hip. In: McCarthy J.C., editor. Early hip disorders: advances in detection and minimally invasive treatment . New York: Springer; 2003:17-44.
8 Matin P. The appearance of bone scans following fractures, including immediate and long term studies. J Nucl Med . 1979;20:1227-1231.
9 Rubin S.J., Marquardt J.D., Gottlieb R.H., et al. Magnetic resonance imaging: a cost-effective alternative to bone scintigraphy in the evaluation of patients with suspected hip fractures. Skeletal Radiol . 1998;27:199-204.
10 Fernbach S.K., Wilkinson R.H. Avulsion injuries of the pelvis and proximal femur. AJR Am J Roentgenol . 1981;137:581-584.
11 Manaster B.J. Adult chronic hip pain: radiographic evaluation. Radiographics . 2000;20:S3-25.
12 Bui-Mansfield L.T., Chew F.S., Lenchik L., et al. Nontraumatic avulsions of the pelvis. AJR Am J Roentgenol . 2002;178:423-427.
13 Resnick D. Physical injury: concepts and terminology. In: Resnick D., editor. Diagnosis of bone and joint disorders . 4th ed. Philadelphia: Saunders; 2002:2643-2658.
14 Duncan T.R., Gerlock A.J.Jr, Muhletaler C.A., et al. Pseudopathologic hip fracture: anatomic explanation. AJR Am J Roentgenol . 1980;135:801-802.
15 Schwappach J.R., Murphey M.D., Kokmeyer S.F., et al. Subcapital fractures of the femoral neck: prevalence and cause of radiographic appearance simulating pathologic fracture. AJR Am J Roentgenol . 1994;162:651-654.
16 Bertin K.C., Harstman J., Coleman S.S. Isolated fracture of the lesser trochanter in adults: an initial manifestation of metastatic malignant disease. J Bone Joint Surg Am . 1984;66:770-773.
3 General Assessment and Optimization for Surgery

Mirek M. Otremba

Medical Assessment of a Patient with a Hip Fracture 25
Epidemiology and Outcome 26
Perioperative Complications 26
Optimal Timing of Surgery 27
Does Delay to Hip Fracture Repair Result in Worse Outcomes? 27
Determinants of Perioperative Risk 28
Surgery-Specific Risk 28
Patient-Specific Risk: Acute Derangements in Physiology and Homeostasis 29
Patient-Specific Risk: Acute Derangements of the Cardiovascular System 29
Cardiac Risk Assessment 29
Cardiac Risk Optimization 30
Coronary Revascularization 30
Beta-Blockers 31
Alpha-2 Agonists 32
Statins 32
Valvular Heart Disease 33
Etiology of the Fracture 33
Fall Resulting in Hip Fracture 33
Pulmonary Risk Assessment and Optimization 34
Diabetes Management and Optimization 34
Liver Disease Assessment and Optimization 35
Perioperative Renal Dysfunction and Optimization of the Patient with Renal Disease 35
Dementia and Delirium 36
Prevention of Venous Thrombosis and Thromboembolism 36
Anticoagulant Management 38
Antiplatelet Agent Management 38
Summary 39

Medical Assessment of a Patient with a Hip Fracture
A patient with a hip fracture presents a challenging, high-risk situation for surgical, anesthetic, and medical consultants. Fracture repair is neither elective nor truly an emergent situation with immediate risk to limb or life of the patient. Bushnell et al classified this type of surgery as “necessary” or urgent. 1 In patients with a hip fracture, the operation is performed as soon as it is safe, and the perioperative medical consultation must be both thorough and rapid. 1 This chapter describes the medical assessment and optimization of a patient hospitalized with a hip fracture. Evidence is available to help guide perioperative planning and risk estimation. Controversy and debate are ongoing about whether these surgical procedures should be delayed for medical optimization, how much delay is acceptable, which medical problems should be optimized, and whether this optimization improves perioperative outcomes.
The medical assessment of the surgical patient includes the following steps ( Table 3-1 ): (1) assessing the cause of the fall that resulted in hip fracture, (2) establishing the patient’s prior comorbidities, (3) assessing any acute physiologic derangements, (4) searching for active cardiac conditions that are known to increase risk, (5) estimating the patient’s risk, (6) refining this risk based on specific investigations, and (7) performing targeted optimization of the patient with an elevated risk in preparation for the surgical procedure. A patient at significant risk for developing a particular outcome (e.g., ischemia, arrhythmia, heart failure, delirium) should also be monitored closely for this event postoperatively (e.g., electrocardiograms and cardiac markers, telemetry, screening for delirium) in an appropriate setting (e.g., intensive care unit [ICU], step-down unit, or ward).
Table 3-1 Steps Involved in the Assessment, Risk Stratification, and Optimization of Acute Hip Fracture Patient Assessment Common Conditions Determine the cause of fall resulting in hip fracture Cardiac syncope Seizure Mechanical fall Establish underlying comorbidities Stroke and transient ischemic attack Coronary artery disease Diabetes Asthma Renal disease Assess for acute physiologic derangements Hyponatremia Hyperglycemia Acute asthma flare Respiratory failure Risk Stratification Conditions and Actions Search for cardiac conditions associated with increased risk 22 Unstable or severe angina Acute congestive heart failure Uncontrolled arrhythmia Severe stenotic valvular disease Estimate patient’s perioperative risk Calculate Revised Cardiac Risk Index Calculate Respiratory Failure Risk Index Perform investigations to refine patient risk Perform echocardiography Obtain dipyridamole technetium cardiac scan Optimization Actions Optimize patient to minimize risk Treat pneumonia Optimize fluid status in congestive heart failure Stabilize arrhythmia Continue specific medications during fasting by the intravenous route, if necessary Treat hyponatremia Manage anticoagulants Ensure deep vein thrombosis prophylaxis

Epidemiology and Outcome
Hip fractures occur most frequently in elderly persons, and the risk of hip fracture increases exponentially with increasing age. 2 In 2004 in the United States, more than 320,000 patients were admitted to the hospital with a hip fracture. 3 This number represents a rate of approximately 850 per 100,000 population. 3 Comparably, in Canada in 2008, there were 456 fractures per 100,000 seniors 4 and 78,554 admissions in 2002 in England. 5 This population has a very high risk of in-hospital mortality, reported to be up to 7%. 4 The 30-day mortality has been reported to be between 5% and 12%, and the reported 1-year mortality is 12% to 37%. 2, 6 The expected mortality in this age group is approximately 10%. 7 Generally, this increased risk of death from hip fracture occurs soon after the event. Leibson et al found that the risk of death at 3 months was 12% in patients who had hip fractures, compared with 3% in aged-matched patients who did not have hip fracture and who were seeking general medical advice (risk ratio, 4). At 1 year, the risk ratio for death fell to 1.8 (20% versus 11%) and to 1.2 after 5 years (52% versus 44%), 2 a decline that, in part, may also represent survivor advantage.
This striking mortality may result from the increasing numbers of comorbidities with age and consequently the higher risk of surgical complications. 8 Most (approximately 88%) of these patients are 65 years old or older, and their mean age is 83 years (range, 52 to 105 years). 4, 8 The average age at presentation is also rising (from 67 years in 1944 to 79 years in 1993). 9 Some of the common comorbidities include dementia (23%), diabetes mellitus (18%), congestive heart failure (CHF; 16%), and chronic obstructive pulmonary disease (COPD; 14%). The presence of these comorbidities has been shown to increase the risk of postoperative complications two- to threefold. 8
Some investigators have implicated age itself as an independent risk factor for perioperative complications. In 2009, Kheterpal et al analyzed more than 7500 patients and identified that age 68 years or older was an independent predictor of perioperative cardiovascular adverse events. 10 Age was also identified as a risk factor for perioperative complications by Detsky et al, 11 as well as in the 2002 version of the American Heart Association/American College of Cardiology guidelines. 12 However, the most widely used preoperative risk stratification index (the Revised Cardiac Risk Index [RCRI]) does not include age as an independent predictor of adverse events. 13
The development of postoperative complications increases mortality rate. Roche et al studied 2448 consecutive patients with acute hip fracture. 5 This population had mortality rates of 9.6% at 30 days and 33% at 1 year, findings similar to those of many other studies. Patients who developed respiratory infections had increased mortality rates of 43% at 30 days and 71% at 1 year. Postoperative CHF was associated with even worse outcomes, mortality rates of 65% at 30 days and 92% at 1 year. Roche et al also found that thromboembolic disease that developed despite prophylactic medications increased mortality rates 4.5-fold. 5 Whether perioperative involvement of medical specialists changes these outcomes is not known.
The high risk of mortality and morbidity requires the entire medical team, including the surgeon, the anesthesiologist, and the internist, to collaborate on the timing of surgery, the preoperative optimization of the patient, the minimizing of postoperative complications, and the appropriate management of any complications that may occur. 14

Perioperative Complications
Common perioperative complications include cardiorespiratory events, delirium, thromboembolism, infections, bleeding, decubitus ulcers, and general deconditioning. 8
Deleterious cardiac outcomes include myocardial infarction, pulmonary edema, ventricular fibrillation, cardiac arrest, and complete heart block. Less serious are supraventricular arrhythmias including atrial fibrillation, demand-driven angina, and mild fluid overload. Pneumonia, exacerbation of underlying lung disease (asthma and COPD), and hypercapnic respiratory failure are commonly encountered postoperative respiratory events. Most physicians concentrate on the cardiac risk and respiratory risk assessment because these parameters are most directly linked to mortality and morbidity and are potentially modifiable. The thromboembolic risk has been well described, and standard protocols to reduce the rates of thromboembolism are recommended in the American College of Chest Physicians (ACCP) guidelines. 15 Some adverse outcomes may have subtle manifestations. For example, in patients with delirium, electrolyte abnormalities, hyperglycemia, and transient renal dysfunction, the diagnosis is often missed or even dismissed.

Optimal Timing of Surgery
The timing of surgery in patients with hip fracture depends on several factors. The availability of operating room time, the availability and preference of orthopaedic surgeons, and medical investigation and optimization potentially contribute to the delay in surgical repair. 6, 16, 17 Orosz et al classified the potential reasons for delay of surgery ( Table 3-2 ). 16 A delay of 24 to 48 hours was the result of delayed routine medical clearance in 52% of patients; in 41% of the patients, the delay was related to unavailability of the operating room or surgeon; and 8% of the patients in this study required medical stabilization. A delay of more than 48 hours resulted from medical clearance issues in 63% of these patients; in 44% of patients, it was caused by unavailability of the surgeon or operating room; and the delay reflected a need for medical stabilization in 35% of these patients. Many of the patients in this study had more than one reason for the postponement of their surgical procedures. 16
Table 3-2 Reasons for Delay from Hospital Arrival to Surgery Awaiting medical consultation or clearance Not having available operating room or surgeon Awaiting family discussion Awaiting laboratory results/other studies Awaiting stabilization of a medical problem Admitting patient too late in the day
Adapted from Orosz GM, Hannan EL, Magaziner J, et al. Hip fracture in the older patient: reasons for delay in hospitalization and timing of surgical repair. J Am Geriatr Soc 2002; 50 :1336-40.
The time of day and the day of the week of admission may further delay the surgery. In a Canadian review of hip operations, patients admitted to hospital between midnight and noon or on weekends were more likely to have their operations within 48 hours. Although this finding seems counterintuitive from the perspective of staffing during these times, this discrepancy may reflect the impact of elective surgery on operating room availability. 17
The timing of surgery may be complicated further by delayed presentation of the patient to the hospital after the incident hip fracture. In a prospective review of 571 patients with hip fracture who presented to 4 major metropolitan hospitals in the United States, 17% of the patients sought help more than 24 hours after the injury. Approximately half of those patients presented more than 72 hours after the initial fall. Most of these patients (77%) did not realize that they had suffered a hip fracture, and some did not present to the hospital earlier because they were unable to communicate their injury to others. 16 Whether this delay contributes to an increased rate of complications and mortality has been addressed by several studies.

Does Delay to Hip Fracture Repair Result in Worse Outcomes?
The timing (delay) of surgery may affect the rate of postoperative complications, functional recovery, functional independence, hospital length of stay, and possibly mortality. Increasing rates of deep vein thrombosis (DVT; ≤62%), decubitus ulcers, infections (pneumonia, urinary tract infections), and loss of bone density and muscle mass have been reported even after a relatively short period of immobility. 8, 16 - 19 These and other variables that remain unaccounted for have the potential to increase mortality rates in patients whose time from injury to surgical treatment is prolonged. 17
Multiple prospective and retrospective studies have tried to address the relationship between timing of surgery and outcomes. If an association between delay and poor outcomes (especially mortality) exists, one must consider whether the delay itself is the culprit or whether it is a marker for patient-related complexity that reflects the need for preoperative testing and optimization (e.g., reversal of anticoagulation, management of decompensated heart failure). 17 Ideally, this association would be better understood from randomized controlled trials. For ethical and feasibility reasons, such studies will likely never be performed. 6 Most data on the effect of surgical delay on patient outcomes are observational. These studies are often prone to bias and may establish association rather than causation.
A meta-analysis by Shiga et al of 16 English-language studies that involved more than 250,000 patients identified an increased risk of 30-day mortality when the operation was delayed by 48 hours after admission (odds ratio, 1.4; number needed to harm, 20). 6 Similarly, there was an increased odds ratio of 1-year mortality of 1.3 (number needed to harm, 40). Unfortunately, the quality of these studies was poor, with an average quality score of 14 out of a maximum of 32. 6 The metaregression determined that delaying operation in patients with low baseline risk and in young patients increased the risk of all-cause mortality. 6 This finding suggests that early surgical intervention may be more beneficial in these patients. Alternatively, the delay resulting from optimization of higher-risk patients may have lowered this group’s mortality rates.
Orosz et al demonstrated the relationships among delay in surgery, comorbidities, and outcome. 20 In a prospective study of 1178 consecutive patients admitted to 4 different hospitals, the hazard ratio for mortality in the early-surgery group (<24 hours) was 0.68 (95% confidence interval [CI], 0.48 to 0.97). After propensity score matching of the two groups, no difference in mortality was noted (odds ratio, 0.98; 95% CI, 0.63 to 1.50). 20 Earlier surgical treatment resulted in fewer days of severe and very severe pain (difference of 0.22 day) and a shorter hospital stay (difference of 1.94 days). Postoperatively, the variables of pain and length of hospital stay were not affected by earlier operation. Early surgical treatment in patients who were medically stable preoperatively resulted in a significant reduction in the incidence of major complications (odds ratio, 0.26; 95% CI, 0.07 to 0.95).
Thus, early surgical treatment is the goal in patients who are medically stable. Delay in seeking medical consultation for the purpose of clearing a patient for surgery (in patients who do not require optimization) increases the incidence of major postoperative complications. In general, delaying patients’ operations for more than 48 hours may increase mortality. Preoperative medical consultation and optimization should be targeted to correcting physiologic abnormalities associated with worse outcomes ( Table 3-3 ). Delaying surgery for more than 48 hours to continue optimization may not be beneficial because of the increased rate of complications (e.g., decubitus ulcers, urinary infections, venous thrombosis) associated with postponement of operation. The role of specific interventions beyond stabilization of physiologic derangements (e.g., beta-blockade, imaging, revascularization) is addressed later in this chapter.
Table 3-3 Acute Medical Conditions Potentially Requiring Assessment and Stabilization Preoperatively System Abnormalities Cardiovascular Hypotension (systolic blood pressure <90 mm Hg) Hypertension (systolic >180 and/or diastolic >110 mm Hg) Respiratory Lower respiratory tract infection (bronchitis, pneumonia) Acute asthma/COPD exacerbation Respiratory failure (P co 2 >55 mm Hg, P o 2 <60 mm Hg, oxygen saturation <90%) Renal Acute renal failure (creatinine >185 μmol/L, urea >14 mmol/L) Electrolyte disturbance (Na <125 or >155 mEq/L, K < 2.5 or >6 mEq/L) Acid-base disturbance (HCO 3 - <18 or >36 mEq/L) Endocrine Uncontrolled diabetes (glucose >25 mmol/L) Thyroid disorders (thyrotoxicosis, hypothyroidism) Hematologic Anemia (hemoglobin <80 g/L) Coagulopathy (INR >1.5)
COPD, chronic obstructive pulmonary disease; HCO 3 - , bicarbonate; INR, international normalized ratio; K, potassium; Na, sodium; P co 2 , partial pressure of carbon dioxide; P o 2 , partial pressure of oxygen.
Adapted from Orosz GM, Magaziner J, Hannan EL, et al. Association of timing of surgery for hip fracture and patient outcomes. JAMA 2004; 291 (14);1738-43.

Determinants of Perioperative Risk
Perioperative risk is the combination of surgery-specific risk and intrinsic patient-specific risk based on preexisting comorbidities and acute physiologic derangements. Determination of this risk can help to guide the team in deciding whether preoperative optimization is necessary or worthwhile and whether patients should be subjected to aggressive postoperative surveillance, monitoring, and management. 10 A patient with a low predicted perioperative risk not only may derive no benefit from optimization, but also may suffer both as a result of the delay and from complications related to unwarranted investigations unrelated to surgery. Conversely, a high-risk patient undergoing a high-risk procedure should be critically evaluated and optimized by the anesthesiologist and medical specialist before the proposed operation. 10, 14
The magnitude of the risk to the patient will determine the degree of invasive monitoring required (arterial lines, central lines, and pulmonary artery catheter) and the appropriate postoperative setting (ICU, step-up unit, cardiac-monitored bed, or general ward bed) after discharge from the postanesthesia care unit. The surgical team may decide on an alternate plan of management (e.g., a nonoperative or less ideal, less invasive procedure) if the patient is deemed to be at too high a risk of complications and mortality.

Surgery-Specific Risk
Factors that contribute to increased surgical risk include the duration of the operation, blood loss, fluid shifts, and the extent of surgical insult resulting from manipulation of bone and soft tissue. Extracapsular fractures often have significant blood loss (≤1 L) associated with the fracture itself, and the surgical procedure may result in further blood loss. 7 Mortality is also increased in patients with these types of fractures (38% 1-year mortality versus 29% in patients with intracapsular fractures). 9 Operative duration of 3.8 hours or longer and administration of 1 or more units of packed red blood cells are independent predictors of adverse cardiac outcomes. 10 Bone marrow instrumentation and application of cement put the patient at a risk of systemic embolization. 14 The surgeon’s expertise will guide the decision about the type of operative management. Total hip replacement performed for subtrochanteric hip fractures is much more invasive and is associated with higher rates of blood loss, fluid shifts, cardiac arrest, and death compared with hip replacement in displaced femoral neck fractures. Pins, intramedullary nails, and other fixation devices are less invasive and consequently are associated with a lower perioperative risk. 14

Patient-Specific Risk: Acute Derangements in Physiology and Homeostasis
Intrinsic patient risk results from the interaction of preexisting comorbidities, functional and cardiac status, and acute physiologic derangements. Patients presenting with a hip fracture often have one or more acute physiologic derangements. These abnormalities may be associated with increased perioperative complications and thus may warrant preoperative correction.
Some common preoperative abnormalities are listed in Table 3-3 . In a prospective cohort study by McLaughlin et al, 34% of patients with hip fracture had minor abnormalities (e.g., systolic blood pressure >180 mm Hg, chest pain with normal electrocardiogram, glucose >25 mmol/L). 8 Major abnormalities (e.g., fever from pneumonia, acute pulmonary edema, severe hyponatremia with serum sodium <125 mEq/L) were present in 23% of patients. The presence of two or more major abnormalities on admission to the hospital was associated with a greater than fourfold increase in postoperative complications. When these major abnormalities were still present preoperatively, the risk of postoperative complications further increased 12-fold. These investigators observed that patients with only minor or no abnormalities preoperatively had a postoperative probability of complications of 7%. That risk increased to 21% in the presence of major abnormalities. 8
To date, no prospective, randomized clinical trials have determined which of these abnormalities and what degree of derangements should be corrected. Most of the literature is expert-based opinion or is derived from nonperioperative settings. Overzealous correction and normalization of abnormalities are often unnecessary and may delay surgical treatment. Rapid correction of abnormalities that are thought to be acute but in fact are chronic may harm the patient. For example, rapid correction of hyponatremia when the sodium concentration is less than 125 mmol/L may result in central pontine myelinolysis with devastating neurologic consequences. 21 Rapid correction of blood pressure in a chronically hypertensive patient may result in cerebral hypoperfusion and stroke, myocardial infarction, or renal failure.

Patient-Specific Risk: Acute Derangements of the Cardiovascular System
The American Heart Association/American College of Cardiology (ACC/AHA) 2007 perioperative guidelines outline several conditions that are major predictors of poor outcome ( Table 3-4 ). In patients undergoing elective surgical procedures, the presence of one or more of these conditions requires further investigation, possible optimization, and delay or cancellation of the operation. 22 In the hip fracture patient, the degree of investigation and optimization is constrained by the short period of time available. It is possible to delay repair of acute hip fracture for up to 48 hours without undue increased risk to the patient (see “Optimal Timing of Surgery,” earlier). Recent myocardial infarction and severe valvular disease optimization require investigations and procedures that may extend past the short time frame available. For example, therapy for severe aortic stenosis requires echocardiographic assessment, surgical consultation, valvular replacement, and postoperative convalescence. Unstable coronary artery disease usually involves assessment with stress testing, angiography, angioplasty, or surgery, even though no evidence supports the use of these interventions perioperatively. Only patients with acute myocardial infarction or patients with hemodynamic instability related to their underlying coronary disease would potentially benefit from such interventions. Conversely, the consultant can potentially intervene and stabilize patients with decompensated heart failure or unstable or uncontrolled arrhythmia and thereby negate the effect of a major predictor of poor cardiac outcome.
Table 3-4 Major Clinical Predictors of Increased Perioperative Cardiac Risk as Defined by 2007 American Heart Association/American College of Cardiology Guidelines Cardiac Condition Indicator Unstable coronary syndrome Myocardial infarction within 30 days Canadian cardiovascular class III or IV angina Unstable angina Decompensated congestive heart failure New-onset heart failure Worsening heart failure Severe symptomatic chronic heart failure (New York Heart Association class IV) Uncontrolled arrhythmia Rapid atrial fibrillation (heart rate >100 beats/min) Ventricular tachycardia Third-degree heart block Symptomatic bradycardia of other origin Severe valvular disease Aortic stenosis with valve area <1.0 cm 2 or a mean gradient >40 mm Hg Severe mitral stenosis (symptomatic of syncope, presyncope, dyspnea, or congestive heart failure)
Adapted from Fleisher LA, Beckman JA, Brown KA, et al. ACC/AHA 2007 Guidelines on perioperative cardiovascular evaluation and care for noncardiac surgery: executive summary. J Am Coll Cardiol 2007; 50 (17):1707-32.

Cardiac Risk Assessment
Estimation of a patient’s perioperative cardiac risk is commonly used in planning for surgery and in directing cardiac investigations with the view of optimizing the patient’s preoperative care before elective operations. The role of risk assessment in a patient with an acute hip fracture is less clear because the evidence of benefit of cardiac optimization is not well defined. Nonetheless, knowledge of the risk of complications should be the basis for educating the patient and his or her family about the expected postoperative course and the perioperative care plan. Cardiac optimization immediately before the operation is discussed later in the chapter.
One of the first systematic attempts of quantifying patients’ perioperative cardiac risk was reported in 1977 by Goldman et al. 23 Subsequently, Detsky et al published a Bayesian approach to establishing patients’ risk. 11 A more recent, and currently most commonly used approach, is the use of the RCRI. 13 Lee at al identified six risk factors as predictors of adverse cardiac outcomes (outcome defined as myocardial infarction, pulmonary edema, ventricular fibrillation, cardiac arrest, and complete heart block) These factors are listed in Table 3-5 . 13 In this system, increasing numbers of factors are associated with an increasing rate of perioperative cardiac events ( Table 3-6 ). This simple risk index has predictive characteristics similar to those of the Goldman and Detsky indices, with reduced complexity and more current patient data reflecting recent advances in surgical and anesthetic techniques. Unfortunately, the data used to derive the RCRI were derived from a population of patients who were undergoing elective noncardiac surgery. 13 This factor may make the index less valid in urgent/emergent surgical patients. Indeed, Detsky et al identified emergency surgery as a high-risk situation with a risk similar to that of recent myocardial infarction, CHF in the week preceding the operation, or moderate to severe coronary artery disease (Canadian Cardiovascular Society class III to IV angina). 11
Table 3-5 Factors Associated with Increased Risk of Perioperative Cardiac Events High-risk type of surgery Ischemic heart disease History of congestive heart failure History of cerebrovascular disease Insulin therapy for diabetes Preoperative serum creatinine >2.0 mg/dL
From Lee TH, Marcantonio ER, Mangione CM, et al. Derivation and prospective validation of a simple index for prediction of cardiac risk of major noncardiac surgery. Circulation 1999; 100 :1043-9.
Table 3-6 Cardiac Event Rates Stratified by Revised Cardiac Risk Index Class Class (No. of Risk Factors) Cardiac Event Rate (%) I (0) 0.4 II (1) 0.9 III (2) 6.6 IV (3 or more) 11.0
From Lee TH, Marcantonio ER, Mangione CM, et al. Derivation and prospective validation of a simple index for prediction of cardiac risk of major noncardiac surgery. Circulation 1999; 100 :1043-9.
A validation study of the Lee cardiac risk index identified orthopaedic surgery in general as low to intermediate risk, with approximately one third of the risk of other intermediate-risk procedures (e.g., abdominal, thoracic, head and neck) and an odds ratio for perioperative cardiac death at 30 days of 2.8 versus 10.3. 24 In the same study, emergency surgery carried a greater than 10-fold increase in risk (6.1% versus 0.5%). 24 The interaction of preexisting patient comorbidity with the emergent nature of hip fracture surgery likely explains the high perioperative mortality rates observed in this patient population. It is likely that the RCRI underestimates risk in the hip fracture patient.

Cardiac Risk Optimization
Optimization of the cardiovascular system should focus on interventions with proven benefit to the patient. Perioperative cardiac complications in hip fracture repair occur in 7% to 12% of patients. 25 In theory, an intervention effective at reducing these complications would produce a large absolute reduction in adverse events. Ideally, a clinician would identify which patients are at the highest risk of cardiovascular events and would offer this therapy to that selected population. The RCRI is the best tool currently available to estimate a patient’s perioperative cardiac risk. Although the index accurately predicts high risk (RCRI class III or IV), most surgical procedures occur in low-risk (RCRI class I or II) patients. 25 Consequently, even though the rate of adverse events in these patients is relatively low, most events occur in this low-risk population. This finding leaves the clinician with difficult decisions about patient selection for specific interventions aimed at reducing cardiac events. To offer an intervention to the total population, one would have to have an effective therapy with minimal risk to the patient. Currently available interventions that may decrease perioperative cardiac events include drug therapy with alpha-2 agonists, beta-blockers, and statins and revascularization procedures (angioplasty with or without stent insertion or coronary artery bypass grafting [CABG]).

Coronary Revascularization
Stress testing and other investigations with the aim of quantifying the degree of underlying coronary disease should be performed only on patients who would benefit from preoperative revascularization. 22 Delaying hip surgery for the sake of cardiac evaluation alone has negative effects on patient outcomes. 26 The current ACC/AHA guidelines emphasize that the decision to revascularize a patient should be based on the patient’s cardiac symptoms and long-term prognosis related to coronary artery disease and not the fact that the patient is to undergo a surgical procedure. 22 Table 3-7 lists the indications for revascularization.
Table 3-7 American Heart Association/American College of Cardiology Guideline Recommendations for Preoperative Coronary Revascularization * Stable angina and known significant (>50%) left main coronary artery disease Stable angina with three-vessel disease (especially if LVEF <50%) Stable angina with two-vessel disease (including proximal LAD stenosis, LVEF <50%, or ischemia on noninvasive testing) High-risk unstable angina or non–ST-elevation myocardial infarction Acute ST-elevation myocardial infarction
LAD, left anterior descending coronary artery; LVEF, left ventricular ejection fraction.
* See text for details.
Adapted from Fleisher LA, Beckman JA, Brown KA, et al. ACC/AHA 2007 Guidelines on perioperative cardiovascular evaluation and care for noncardiac surgery: executive summary. J Am Coll Cardiol 2007; 50 (17):1707-32.
The data to support the role of perioperative CABG are derived predominantly from patients undergoing vascular surgery, high-risk abdominal operations, and thoracic surgical procedures. Indeed, the guideline authors indicate that the available data for revascularization before orthopaedic procedures do not support this practice. 22 Most of the studies were performed in elective surgical patients, and the largest randomized trial of revascularization had a delay of 48 days before vascular surgery. 27 Any similar delay in urgent hip fracture repair likely would be detrimental to the patient, and the benefits of revascularization for stable angina would be overshadowed by the complications of immobility.
Percutaneous coronary interventions do not play a significant role in perioperative risk reduction for the patient with stable angina. 22 Acute myocardial infarction occurring before the surgical procedure carries with it major morbidity and mortality risk that should be addressed before hip repair. Coronary angioplasty allows for the minimum delay from the procedure to surgery (2 to 4 weeks). Angioplasty with bare metal stent insertion usually requires a 4- to 6-week delay before surgical intervention to minimize stent thrombosis. The recommendations for delay of treatment are based on the finding that interruption of dual antiplatelet therapy (aspirin and a thienopyridine such as clopidogrel) is associated with a high rate of reinfarction. This delay can potentially be decreased if the surgeon and the patient accept the risk of increased bleeding attributed to dual antiplatelet therapy and the increased risk of myocardial infarction. The ACCP 2008 thrombosis guidelines recommend continuation of dual antiplatelet agents perioperatively. 15 This recommendation is based on the value of prevention of stent thrombosis while recognizing the higher chance of perioperative bleeding. 15 In these complicated situations, expert advice from the interventional cardiologist who will be performing the procedure is essential to help guide perioperative management of the orthopaedic patient.

Beta-Blockers
Surgery is associated with a transient rise in catecholamines. The resultant elevation of blood pressure and heart rate increase myocardial oxygen demand, which may lead to myocardial ischemia and infarction. Reducing the effect of catecholamines with the use of perioperative beta-blockers has been proposed as a way to decrease myocardial ischemia and other cardiac events. Mangano et al were among the first investigators to test this hypothesis with atenolol in a placebo-controlled, randomized trial of 200 patients undergoing noncardiac surgery. 28 This intervention was started immediately preoperatively and was continued for up to 7 days postoperatively. The investigators observed a mortality reduction from 14% to 3% at 1 year following the surgical procedure. 28 Subsequently, multiple studies showed variable effects of beta-blockers on perioperative cardiovascular morbidity and mortality (reduction, no difference, and increased rates of bradycardia and hypotension). 29 In 2006 and then in 2007, the ACC/AHA task force summarized the available data and published guidelines on the use of perioperative beta-blockers. 30
Results of two of the largest randomized trials of beta-blockers in this context were published after the 2007 ACC/AHA guidelines: POISE in 2008 and DECREASE-IV in 2009. 31, 32 Table 3-8 outlines the salient features and outcomes of these two trials. The major differences between the two trials were the use of the type of beta-blocker (extended-release metoprolol in POISE, bisoprolol in DECREASE-IV), the average dose of beta-blocker, and, probably most important, the protocol for initiation of beta-blockade. The POISE protocol called for starting metoprolol at 100 mg 2 to 4 hours preoperatively and then increasing the dose to 200 mg daily (if tolerated) 12 hours after the initial dose and continuing that dose for 30 days. The DECREASE-IV protocol started bisoprolol at 2.5 mg daily (equivalent dose of extended-release metoprolol of 50 mg daily) and titrated the dose in steps of 1.25 mg or 2.5 mg to a target heart rate of 50 to 70 beats/minute. Both trials reduced the incidence of postoperative cardiac complications (absolute risk reduction of 1.1% in POISE and 3.9% in DECREASE-IV). Unexpectedly, more patients in the treatment group of the POISE trial suffered a stroke, and the 30-day total mortality rate was increased by 0.8% (from stroke and sepsis). In DECREASE-IV, investigators noted no increase in mortality rate in the bisoprolol group, and there was a nonstatistically significant trend toward decreased mortality (1.8% in treatment group versus 3.0% in placebo group). The higher mortality rate observed in POISE may potentially be explained by the loading regimen and the dose of beta-blockers. It appears that a more gentle initiation of treatment and a gradual achievement of a steady state are required for beta-blockers to have a positive effect. 29 In the hip fracture patient, the window to initiate beta-blockade is very short (<48 hours) and likely would not decrease patients’ mortality risk.

Table 3-8 Comparison of the Largest Perioperative Beta-Blocker in Noncardiac Surgery Trials: POISE and DECREASE-IV
Thus, in a patient with hip fracture, current evidence does not support the preoperative initiation of beta-blocker treatment for the purpose of reducing perioperative cardiovascular events. If the patient is already receiving a beta-blocker, this agent should be continued perioperatively because acute withdrawal from this medication may result in myocardial ischemia, infarction, arrhythmia, and sudden death. 22 The use of beta-blockade for other indications (e.g., rate control of atrial fibrillation) in these patients is likely safe, and treatment with beta-blockers may need to be initiated preoperatively to reduce morbidity and mortality related to arrhythmia. 22 If the patient is unable to take oral medication, beta-blockers should be administered by the intravenous route to avoid medication withdrawal.

Alpha-2 Agonists
Centrally acting alpha-2 agonists reduce brainstem-mediated sympathetic system activation. Clonidine and mivazerol have been studied in the perioperative setting with variable efficacy. The ACC/AHA do not recommend these drugs solely for perioperative cardiac risk reduction until further data supporting the use of these drugs are published. The current recommended possible use of alpha-2 agonists is to control hypertension in surgical patients with known coronary artery disease or at least one cardiac risk factor. 22

Statins
Lipid-lowering therapy with statins (3-hydroxy-3-methyl-glutaryl–coenzyme A [HMG-CoA] reductase inhibitors) has been shown to prevent cardiac events in patients with preexisting coronary disease or those at risk of heart disease. Whether this benefit extends to patients in the perioperative setting is largely unknown. Most of the evidence for the perioperative use of statins comes from nonrandomized studies. The largest study was performed by Lindenauer et al in an administrative database review, in which 77,082 statin-using patients who were undergoing major noncardiac surgical procedures were compared with 780,591 controls. Patients receiving statins had significantly lower mortality rates (an odds ratio of 0.62) compared with patients not receiving statins. 33 The two randomized trials of perioperative statin therapy showed inconsistent effects. Durazzo et al randomly assigned 100 patients who were undergoing vascular surgery to atorvastatin 20 mg daily or placebo for 30 days preoperatively. 34 Subjects in the treatment arm of the trial had a significant reduction in cardiac events (4 patients [8%] versus 13 patients [26%]). 34
A larger and more recent study (DECREASE-IV) by Dunkelgrun et al with fluvastatin failed to confirm this finding in a noncardiac surgical population in which 1066 patients were randomly assigned to 80 mg of fluvastatin XL or placebo an average of 34 days before the operation. 32 The treatment group had a 3.2% cardiac event rate, compared with a 4.9% rate in the placebo arm. This finding was not statistically significant. 32 The current recommendations from the ACC/AHA state that patients already receiving a statin medication should continue their medication perioperatively. Patients at increased risk for cardiac disease may be considered for this treatment, although the evidence for this recommendation came before the completion of the DECREASE-IV study. 22 Furthermore, both randomized trials treated their patients for a month before the surgical procedure, based on the theory of coronary plaque stabilization with statin medication. 32 Patients with hip fracture have insufficient time for this stabilization to be achieved, and hence the role of statins for perioperative risk reduction may be limited. Initiation of a statin medication before hip surgery is currently not supported by the evidence. However, this approach may be considered for the prevention of future adverse events in a patient at risk for cardiovascular disease, although the use of these drugs may be more effective postoperatively, to avoid potential drug interactions and adverse reactions to the HMG CoA reductase inhibitors.

Valvular Heart Disease
Symptomatic aortic stenosis is fairly rare in orthopaedic patients. Salerno et al found that only 1 patient out of 338 consecutive patients evaluated preoperatively by internists had significant aortic stenosis. 25 The presence of severe aortic stenosis carries a severalfold increase in perioperative cardiac risk. Goldman found that severe aortic stenosis carried a 6.3-fold risk for perioperative cardiac events. 35 Kertai et al found this risk to be 5.2-fold higher for patients with any significant aortic stenosis (gradient >25 mm Hg). 36 The absolute risk of events in all the patients with aortic stenosis in this study was 14%. Moderate aortic stenosis (defined by Kertai et al as a gradient of 25 to 49 mm Hg or a valve area of 0.7 to 1 cm 2 ) carried a risk of 11%, whereas severe aortic stenosis (gradient ≥50 mm Hg or valve area <0.7 cm 2 ) was associated with a risk of 31%. 36 Currently, the only urgent treatment for severe aortic stenosis is valvuloplasty because valve replacement and recovery from the procedure are not usually feasible in the hip fracture patient. Valve replacement has a very high rate of periprocedural complications and is not routinely recommended for patients with severe aortic stenosis who are undergoing urgent hip fracture operations, although no randomized trial data exist for this population. 22
Severe mitral stenosis is also a poorly tolerated lesion perioperatively. Valvuloplasty may be a better choice than valve replacement in this patient population, and an opinion from an experienced interventional cardiologist should be obtained before the hip procedure is performed. 22 Regurgitant mitral valve lesions are usually better tolerated during surgery, although increases in afterload (by elevated blood pressure) should be limited. Careful fluid management and control of arrhythmias should be priorities in caring for these patients, to prevent postoperative CHF.

Etiology of the Fracture
Hip fractures are usually the result of falls in a patient with a condition predisposing to hip fracture. Approximately half of these patients have osteoporosis. Most of the remaining patients have osteopenia. Only approximately 3% of patients have a localized bone abnormality, such as a tumor (primary or metastatic), bone cyst, or Paget’s disease. 7 To prevent further fractures after the initial repair, treatment of the underlying osteopenia should be instituted. Currently, most patients are treated with calcium, vitamin D, and a bisphosphonate. Most of the evidence favors the use of bisphosphonates, and the evidence on whether calcium and vitamin D may prevent further fractures is conflicting. 7 Elderly and institutionalized patients have a high incidence of vitamin D deficiency, and the side effects and cost of this therapy are low. Preventing further fractures may further reduce mortality in these patients.

Fall Resulting in Hip Fracture
Most hip fractures are the result of falls. 7, 37 Up to one third of persons 65 years old and older will fall yearly, and the risk of falling increases with age in both sexes. In a community-based setting, falls are more common in women (≤81%) ( Table 3-9 ). 7, 9, 38 A search for a medical cause of the fall should be attempted. 7 Falls are usually the result of a combination of environmental and host factors. 37 Host factors include neurologic, cerebrovascular, and cardiovascular conditions. Alternatively, falls result from a combination of age-related degenerative diseases that decrease muscle strength, alter sensory perception, and produce abnormal gait and coordination. 37, 38 Postural hypotension further increases the risk of falling in frail elderly patients. 7 Medications are often cited as causative agents for falls, although Lee et al demonstrated that the risk is mostly explained by the underlying illness (e.g., eye disease, heart disease, lower musculoskeletal pain), with the exception of medications for diabetes. 38 Syncope, although commonly assessed as a causative factor for falls, is found in only a small (3% to 4%) proportion of patients. 37

Table 3-9 Incidence of Falls in the Community*
Even though the percentage of falls caused by syncope is small, the reasons for syncope may result in increased perioperative mortality and morbidity. Some common causes of syncope are listed in Table 3-10 . The medical assessment of the hip fracture patient with syncope should include a thorough exploration of symptoms and a physical examination directed at detecting the cause of the syncope. If a medical cause is found, the clinician should attempt to reverse the underlying physiologic disturbance and optimize the patient’s cardiac status, to reduce the recurrence of falls and prepare the patient for the surgical procedure.
Table 3-10 Common Causes of Syncope That May Result in Hip Fracture Category of Disorder Common Conditions Valvular disease Aortic stenosis Mitral stenosis Arrhythmia Complete heart block Ventricular tachycardia Atrial fibrillation in the presence of stenotic valvular disease or LV dysfunction Coronary artery disease Myocardial infarction Other cardiovascular disease Pulmonary embolism Hypertrophic cardiomyopathy Pulmonary hypertension Neurogenic disorder Seizure Autonomic neuropathy resulting in postural hypotension Cerebrovascular disorder Transient ischemic attack Stroke Vertebrobasilar insufficiency Metabolic disorder Hypoglycemia Severe anemia Hypoxemia Other Anxiety/panic attacks Mechanical fall resulting in head injury
LV, left ventricular.

Pulmonary Risk Assessment and Optimization
Common postoperative respiratory problems include the development of pneumonia, respiratory failure, prolonged need for mechanical ventilation, exacerbation of underlying COPD, and asthma. 39, 40 Lawrence et al described a large cohort of 8930 patients with hip fracture, 4% of whom suffered pulmonary complications. 39 This rate is comparable to the rate seen in general elective surgical population. 40 Respiratory complications are most commonly seen in patients undergoing either thoracic or abdominal procedures because these operations interfere directly with normal physiologic function of the lungs. Elective hip surgery usually has low risk of pulmonary complications. The increased risk seen in patients with hip fracture likely results from an increased burden of comorbid illness (as evidenced by high American Society of Anesthesiologists physical status class), an aged population, and the emergency nature of the operation. 40
Strategies to decrease pulmonary complications have been validated only in abdominal surgery and include lung expansion maneuvers (e.g., incentive spirometry, deep breathing exercises), nasogastric decompression, and a laparoscopic surgical approach. 41 These strategies likely would not have a similar impact in orthopaedic patients unless acute abdominal complications developed postoperatively.
Treatment of acute exacerbations of COPD and asthma with beta-agonists, anticholinergic bronchodilators, steroids, and antibiotics (when patients have signs of an acute infection resulting in increased sputum production, a change in sputum color, or airspace disease visible on a chest radiograph) should be attempted preoperatively. 40 How long to delay the operation for the treatment to take effect is unknown, but in general the patient should show a degree of clinical improvement in respiratory status, resolution of fever, improving oxygenation, and decreasing airway reactivity. The preoperative use of corticosteroids is safe and does not result in increased postoperative wound issues. Corticosteroids should not be withheld from patients with obstructive lung disease. 40
Assessment of COPD or asthma severity with spirometry is difficult in a bedridden patient and has not been shown to predict or improve perioperative outcomes. Indeed, an abnormal physical examination of the respiratory system and an abnormal chest radiograph are better at predicting pulmonary complications (odds ratios, 5.8 and 3.2, respectively). 40 Validated factors to predict postoperative respiratory failure and pneumonia are shown in Table 3-11 . Smoking cessation is impractical in this short period, and the clinician should focus on minimizing the impact of nicotine withdrawal by providing nicotine replacement therapy. Any contact with the health care system should also include counseling the patient about smoking cessation after hospital discharge.
Table 3-11 Clinical Variables Associated with Postoperative Respiratory Complications * Clinical Variable Increased Risk of Pneumonia Increased Risk of Respiratory Failure Chronic obstructive pulmonary disease Yes Yes Advanced age Yes (³80) Yes (³70) Functional dependency Yes Yes Albumin <30 g/L No Yes Blood urea nitrogen ³30 mg/dL Yes Yes Weight loss Yes No
* Increasing numbers of variables increase the risk of complications.
Data from Arozullah AM, Daley J, Henderson WG, et al. Multifactorial risk index for predicting postoperative respiratory failure in men after major noncardiac surgery: the National Veterans Administration Surgical Quality Improvement Program. Ann Surg 2000; 232 :242–53; and Arozullah AM, Khuri SF, Henderson WG, et al. Development and validation of a multifactorial risk index for predicting postoperative pneumonia after major noncardiac surgery. Ann Intern Med 2001; 135 :847-57.

Diabetes Management and Optimization
Patients with diabetes have a twofold higher prevalence of ischemic heart disease and a higher risk of perioperative cardiac complications than do nondiabetic patients. 13, 42 Often the underlying coronary disease may be asymptomatic (silent). 42 Cardiac risk assessment is discussed in detail elsewhere in the chapter, and this section focuses mainly on glucose and medication management.
Stress related to hip fracture, surgery, and anesthesia increases catecholamine and cortisol levels, with resultant increases in insulin resistance and, in a diabetic patient, blood glucose levels. 43 Patients with previously well-controlled diabetes may have marked hyperglycemia in the perioperative setting. This hyperglycemia, in turn, may result in osmotic diuresis, dehydration, electrolyte disturbances, poor wound healing, and increased risk of wound and other infections. 43 Preoperative blood glucose concentrations higher than 35 mmol/L have been associated with worse perioperative outcomes in hip fracture surgery. 8 Management of the diabetic patient should be aimed at maintaining relatively normal blood glucose levels, and a priority should be placed on preventing hypoglycemia, which may result in neurologic compromise and cardiac ischemia. The optimal level of blood glucose is unknown. Aggressive glucose control has been studied in ICU populations, with conflicting results. No prospective studies of glucose management in non-ICU surgical patients have been conducted, 42 and most recommendations are based on expert opinion. In general, a glucose level between 8 and 11 mmol/L (150 to 200 mg/dL) is a reasonable goal and minimizes the risk of hypoglycemia. 42, 43
Dietary carbohydrate intake in patients awaiting hip fracture repair is variable, and often patients are fasting in anticipation of the upcoming operation. Oral hypoglycemic medications should be withheld during this time. 42, 43 Sulfonylureas (e.g., glyburide, gliclazide) and mitiglinide analogues (e.g., repaglinide) put a patient at a high risk of hypoglycemia. Biguanides (metformin) can result in lactic acidosis in the perioperative period, and thiazolidinediones (rosiglitazone, pioglitazone) increase the risk of heart failure. These medications should be replaced with a supplemental short-acting insulin analogue, at a dose based on frequent (every 6 hours) blood glucose determinations. 43 Patients taking multiple oral agents may benefit from the addition of a basal-type insulin (e.g., NPH, glargine, detemir) once or twice daily to prevent hyperglycemia when oral agents are withheld.
Patients with type 1 diabetes should have their basal insulin continued or be managed by intravenous insulin infusion even when they are not eating (supplemental intravenous dextrose may be required to maintain euglycemia), to prevent the development of ketoacidosis. Patients with type 2 diabetes should have 50% to 60% of their total insulin dose given to them as basal insulin (either twice daily for NPH and detemir or once daily for glargine) while they are in a fasting state. A supplemental short-acting insulin is prescribed to manage hyperglycemia. Patients with type 2 diabetes who are taking large doses of insulin (>100 units/day) may also be managed with an intravenous insulin infusion. Detailed insulin management is beyond the scope of this chapter and is described in detail in the literature. 43 Once the patient is able to eat a full diet, the previous diabetes regimen should be resumed.

Liver Disease Assessment and Optimization
Patients with liver disease and cirrhosis have higher rates of osteopenia and traumatic bone fractures than do other patients. 44 The prevalence of liver disease is also on the rise in the population at large. Patients are often unaware of underlying liver dysfunction, and a careful history and physical examination may point to the underlying liver disease and cirrhosis. Routine screening without clinical suspicion of liver disease is of low yield and likely will not improve outcomes. 45 Data on hip surgery in patients with cirrhosis are limited, but published series note several trends. One of the most important predictors of perioperative morbidity and mortality seems to be directly proportional to the severity of liver disease, as measured by the Child-Pugh classification (in which increasing numbers of poor outcome predictors—ascites, encephalopathy, hyperbilirubinemia, hypoalbuminemia, increasing international normalized ratio [INR]—correlate with higher class). Patients with class A liver cirrhosis have a fairly low risk of complications (5% to 14%). This rate increases in class B to 28% to 55% and class C to 100%. 44, 46 Urgent hip arthroplasties have worse outcomes compared with elective hip replacements (≤80% rate of morbidity and mortality) and are associated with increased transfusion requirements, longer operative time, increased length of hospital stay, and increased rates of liver decompensation. 44
The role of the medical consultant is to identify the patient with liver disease and improve the patient’s preoperative status by correcting ascites, encephalopathy, and increased INR. Hyperbilirubinemia and hypoalbuminemia are more difficult to correct in the short timeframe available before hip surgery. Although no prospective data exist to confirm this clinical practice, lowering the patient’s Child-Pugh score presumably will result in improved outcomes. A detailed discussion of management of these abnormalities is beyond the scope of this chapter, and current guidelines should be consulted. Patients with Child-Pugh class C cirrhosis or acute, fulminant, or alcoholic hepatitis have very poor perioperative outcome, and surgery is usually contraindicated. 45

Perioperative Renal Dysfunction and Optimization of the Patient with Renal Disease
The perioperative development of acute renal failure (ARF) is relatively uncommon. Approximately 1% of patients with previously normal renal function will develop renal failure. 47 Preexisting renal dysfunction is associated with threefold increase in perioperative cardiac risk (as estimated by the RCRI). 13 The postoperative development of renal failure is associated with further increases in morbidity and mortality and often results in incomplete recovery of renal function in patients who survive the perioperative period. 48 Only approximately 15% of patients who develop ARF will fully recover. Mortality associated with ARF may approach 30% to 50%. 47, 48 Of the patients who survive, 5% will have permanent renal failure, 5% will recover incompletely and continue to have declining renal function, and another 15% will recover with some degree of renal impairment. Older and sicker patients are at particular risk of unfavorable outcomes. 48
Patients at increased risk for development of ARF include those of advanced age and those with preexisting renal insufficiency, diabetes, and CHF. Several medications may put the vulnerable kidney at further risk. These drugs include diuretics, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, nonsteroidal anti-inflammatory medications, and cyclooxygenase 2 (COX-2) inhibitors. 48 Withholding these medications may reduce the risk of renal injury. Further injury may result from administration of intravenous contrast media for computed tomography scanning, and the use of intravenous dye should be avoided in patients with known renal dysfunction. 48 Adequate hydration may prevent hypoperfusion injury in a patient with poor preoperative oral intake and in whom significant blood loss may occur intraoperatively.

Dementia and Delirium
Increasing age is associated with increasing rates of cognitive impairment or dementia. The risk of postoperative delirium may be as high as 45% to 61%. 49 Several factors contribute to increasing rates of delirium and include advanced age, alcohol abuse, underlying cognitive and physical impairment, electrolyte imbalances, and abnormal glucose homeostasis ( Table 3-12 ). 50
Table 3-12 Risk Factors for Development of Postoperative Delirium Advanced age (≥70 yr) Substance abuse (alcohol) Cognitive impairment and dementia (Mini-Mental State Exam score <24) Sensory impairment (visual acuity worse than 20/70) Poor functional status (Acute Physiology and Chronic Health Evaluation [APACHE] II score >16) Electrolyte abnormalities (sodium <130 or >150 mmol/L, potassium <3.0 or >6.0 mmol/L Dehydration Abnormal glucose levels (glucose <3.3 or >16.7 mmol/L [<60 or >300 mg/dL]) Depression Psychoactive medications (anticholinergics, benzodiazepines)
Data from Marcantonio ER, Goldman L, Mangione CM, et al. A clinical prediction rule for delirium after elective noncardiac surgery. JAMA 1994; 271 (2):134-9; Kalisvaart KJ, De Jonghe JFM, Bogaards MJ, et al. Haloperidol prophylaxis for elderly hip-surgery patients at risk for delirium: a randomized placebo-controlled study. J Am Geriatr Soc 2005; 53 :1658-66; and Smith PJ, Attix DK, Weldon BC, et al. Executive function and depression as independent risk factors for postoperative delirium. Anesthesiology 2009; 110 :781-7.
The development of postoperative delirium is associated with higher mortality rates, increased rates of complications, poorer functional recovery, and a longer length of hospital stay. 50 Strategies to reduce the incidence of delirium include consultation and management of patients by a geriatric team, correction of electrolyte abnormalities, ensuring of proper nutrition, adequate treatment of severe pain, and discontinuation of high-risk medications ( Table 3-13 ). 51
Table 3-13 Drugs Commonly Associated with Increased Risk of Delirium Medication Class Examples Anticholinergics Antihistamines (diphenhydramine, hydroxyzine) Antiparkinsonians (levodopa) Antispasmodics (tolterodine) Benzodiazepines Lorazepam, alprazolam Opiates Meperidine H 2 -receptor blockers Cimetidine
From Palmer RM: Perioperative care of the elderly patient. Cleve Clin J Med 2006; 73 :S106-10.
The use of medical therapy with haloperidol to prevent delirium is not successful in reducing the incidence of this complication. Kalisvaart et al randomized patients at medium to high risk of delirium to haloperidol (Haldol) around the time of hip surgery. 52 Patients in this study had two or more of the following risk factors for perioperative delirium: visual impairment, Acute Physiology and Chronic Health Evaluation (APACHE) II scores higher than 16, cognitive impairment, or laboratory evidence of dehydration (urea-to-creatinine ratio ≥18). The administration of haloperidol at a dose of 1.5 mg per day in three divided doses was associated with decreased severity and duration of delirium, as well as decreased length of hospital stay. The incidence of delirium was not reduced, however. 52
Reducing the rates of delirium potentially will result in improved patient outcomes. Careful attention to risk factors, preoperative correction of physiologic derangements, and preoperative pain control are the key strategies for decreasing the incidence of delirium. Medical therapy with antipsychotic medication has little role to play in the prevention of delirium in the hip fracture patient, but it may be helpful in selected patients.

Prevention of Venous Thrombosis and Thromboembolism
Venous thromboembolism (VTE) occurs frequently in the perioperative setting in patients with hip fracture. This population has one of the highest risks during the perioperative period (general surgical procedures and urologic and gynecologic operations carry about half this risk). Without prophylaxis, venographically proven DVT occurs in up to 60% to 80% of patients. 15, 18 Proximal DVTs can be detected in 23% to 30% of these hip fracture patients. Thus, about one half of the DVTs are asymptomatic and resolve spontaneously. Despite this high rate of resolution, pulmonary embolism (PE) occurs in 3% to 11% of patients. Fatal PEs have been reported in 0.3% to 7.5% of patients with hip fracture.
Although it is common, VTE is not universal in this patient group. Table 3-14 lists risk factors that increase the probability of development of perioperative DVT/PE. Currently, no validated risk score is available to help stratify patients according to their underlying risk. Thus, routine prophylaxis in most patients is recommended by the ACCP. 15 Fondaparinux has the most robust trial data to support its use, but all other modalities listed in Table 3-15 are thought to be effective in preventing DVT and PE. The use of aspirin is not recommended as the sole method of prophylaxis. 15
Table 3-14 Risk Factors for Venous Thromboembolism in Patients with Hip Fracture Increasing age Previous venous thromboembolism Inherited or acquired thrombophilia Estrogen-containing therapy Immobility Delay in surgical repair Malignancy Acute medical illness
Adapted from Geerts WH, Bergqvist D, Pineo GF, et al. Prevention of venous thromboembolism: American College of Chest Physicians evidence-based clinical practice guidelines (8th edition). Chest 2008; 133 :381S-453S.
Table 3-15 Recommended Regimens for Perioperative Thromboprophylaxis * Agent or Device Regimen or Approach Low-dose unfractionated heparin Heparin 5000 units SC tid Low-molecular-weight heparin Dalteparin 5000 units SC daily Enoxaparin 40 mg SC daily Synthetic factor Xa inhibitors Fondaparinux 2.5 mg SC daily † Vitamin K antagonist Warfarin (target INR 2.0-3.0) Mechanical devices Graduated compression stockings Intermittent pneumatic compression Venous foot pump
INR, international normalized ratio; SC, subcutaneously; tid, three times daily.
* See text for details.
† Received the highest grade of recommendation.
Adapted from Geerts WH, Bergqvist D, Pineo GF, et al. Prevention of venous thromboembolism: American College of Chest Physicians evidence-based clinical practice guidelines (8th edition). Chest 2008; 133 :381S-453S.
The routine use of thromboprophylaxis has made fatal PE uncommon. The rates of symptomatic VTE have declined to between 1.3% and 10%. Most of these events occur after hospital discharge and may result in high rates of readmission. 15 The recommended extension of treatment with fondaparinux (a direct factor Xa inhibitor) from 1 to 4 weeks has resulted in a reduction of venographic DVT rates from 35.0% to 1.4% (relative risk reduction [RRR], 96%). Symptomatic thromboembolism rates have decreased from 2.7% to 0.3% (RRR, 89%). Extension of treatment with low-molecular-weight heparin (LMWH) from 2 to 6 weeks has resulted in a decrease of symptomatic VTE from 5.2% to 1.2%. This extended prophylaxis time has not been associated with an increased risk of major bleeding. The 2008 ACCP guidelines recommend the duration of prophylaxis for hip fracture surgery for a minimum 10 days and for up to 35 days postoperatively with fondaparinux, LMWH, or a vitamin K antagonist. 15
Perioperative bleeding is the potential major side effect of anticoagulant use. Most studies to date have found very little evidence of a statistically significant increase in the risk of bleeding. 15 Mechanical thromboprophylaxis should be preferentially employed in patients deemed to be at high risk of bleeding. Anticoagulants should be started preoperatively if a significant delay to operative treatment is expected (e.g., for medical optimization, testing, or because of a lack of operating room time). In a small study of 21 patients, Zahn et al found that after a 48-hour delay in surgery, 62% of patients developed DVT (all on the same side as the fracture, but one third of DVTs were bilateral). 19
Preoperative administration of an anticoagulant may result in an increased risk of bleeding that may outweigh the risk reduction of formation of a thrombus. Most patients can be started safely on prophylactic-dose anticoagulants 6 hours postoperatively, especially when concern for intraoperative bleeding exists. Patients in whom neuraxial (epidural) anesthesia is being considered should have their anticoagulant treatment either interrupted or delayed before placement or removal of these catheters, to prevent the formation of epidural hematoma and the development of potentially catastrophic neurologic sequelae. The anesthesiologist should be acutely aware of the plan for thromboprophylaxis and treatment of VTE, to help guide the timing and choice of anticoagulants, the anesthetic plan, and the postoperative pain control regimen.
A promising newer class of oral anticoagulant (rivaroxaban, a factor Xa inhibitor) has been shown to be more effective than enoxaparin in patients undergoing elective hip and knee arthroplasties. The oral drug resulted in a further 31% RRR (3.2% absolute risk reduction) of VTE in patients undergoing knee operations. 53,54 At this time, the drug has not been approved for use in the United States, and there is no evidence of its use in hip fracture. Rivaroxaban is associated with a somewhat higher (albeit not statistically significant) risk of bleeding in comparison with enoxaparin. 53, 54 Further experience and research with this drug will be needed before routine use can be recommended in the hip fracture population.

Anticoagulant Management
Patients who take anticoagulants on a long-term basis may present to the hospital. Common reasons to take long-term anticoagulant therapy include atrial fibrillation, previous VTE, or mechanical cardiac valves. Patients taking preoperative anticoagulation should be assessed for the risk of interruption of the anticoagulant (most commonly warfarin) in the perioperative period. The decision whether to bridge anticoagulant use in these patients with a full dose of heparin (either subcutaneous LMWH or intravenous unfractionated heparin) while the effect of warfarin is reversed should be based on the risk of thromboembolism while the anticoagulant is withheld. Reversal of warfarin before hip fracture surgery should be accomplished with low doses of vitamin K (2.5 to 5 mg orally), and fresh frozen plasma (or any other prothrombin concentrate) should be limited to patients requiring immediate reversal of warfarin’s effect. 55 Patients with mechanical heart valves, atrial fibrillation, or VTE who are at high risk for thromboembolism should be treated with therapeutic doses of heparin ( Table 3-16 ). Moderate-risk patients ( Table 3-17 ) should be treated either with therapeutic doses of heparin or low-dose LMWH (e.g., enoxaparin 40 mg subcutaneously daily). Patients at low risk of thromboembolism can safely have their oral anticoagulant reversed and then reinitiated shortly postoperatively, simultaneously with DVT prophylaxis.
Table 3-16 Patient Characteristics Resulting in High Risk of Thromboembolism Mechanical mitral valve prosthesis Any mechanical valve with recent (≤6 mo) stroke or TIA Atrial fibrillation with recent (≤3 mo) stroke or TIA Atrial fibrillation resulting from rheumatic valvular heart disease Atrial fibrillation with history of stroke and three or more stroke risk factors * Recent VTE (≤3 mo) VTE and severe thrombophilia †
TIA, transient ischemic attack; VTE, venous thromboembolism.
* Stroke risk factors include age >75 yr, congestive heart failure history, diabetes, and hypertension.
† Severe thrombophilic risk factors include the following: deficiency of protein C, S, or antithrombin; antiphospholipid antibodies; and multiple abnormalities.
Adapted from Douketis JD, Berger PB, Dunn AS, et al. The perioperative management of antithrombotic therapy. Chest 2008; 133 :299S-339S.
Table 3-17 Patient Characteristics Resulting in Moderate Risk of Thromboembolism Mechanical aortic valve prosthesis with atrial fibrillation or one or more stroke risk factors * Atrial fibrillation with history of stroke and one other stroke risk factor * Atrial fibrillation with three or more stroke risk factors * Thromboembolism 3-12 mo preoperatively VTE and nonmajor thrombophilic conditions † Recurrent VTE VTE and active cancer
VTE, venous thromboembolism.
* Stroke risk factors include age >75 yr, congestive heart failure history, diabetes, and hypertension.
† Nonmajor thrombophilic risk factors include factor V Leiden or factor II heterozygote.
Adapted from Douketis JD, Berger PB, Dunn AS, et al. The perioperative management of antithrombotic therapy. Chest 2008; 133 :299S-339S.

Antiplatelet Agent Management
Antiplatelet agents commonly used for prevention of cardiovascular and cerebrovascular disease include acetylsalicylic acid (aspirin), clopidogrel, and dipyridamole. Aspirin and clopidogrel irreversibly block the function of platelet aggregation, and their action extends up to the life span of platelets. Thus, it takes 7 to 10 days to normalize a patient’s platelet function. Dipyridamole reversibly inhibits platelet function, and its effect is lost within 24 to 48 hours. In common practice, dipyridamole is prescribed along with aspirin (200 mg dipyridamole, 25 mg aspirin twice daily), and the effect of this combination on the platelets extends to 7 to 10 days. In the hip fracture patient, the presence of aspirin preoperatively is associated with a slightly increased risk of bleeding (absolute risk increase, 0.5%). Patients at increased risk of coronary events are advised to continue taking aspirin, if possible, to minimize cardiac risk. Antiplatelet agents should be resumed 24 hours postoperatively. 55
If aspirin and clopidogrel are used in a patient with a coronary stent, consultation with an interventional cardiologist may be desired. Discontinuation of antiplatelet agents may result in stent thrombosis, acute myocardial infarction, and death. Generally, patients with bare metal stents should have a minimum of 6 weeks of dual antiplatelet therapy before clopidogrel treatment can be interrupted, and aspirin therapy should be continued perioperatively. Clopidogrel should be restarted postoperatively as soon as possible. Patients with drug-eluting stents should have a minimum of 1 year of dual antiplatelet therapy before discontinuation of clopidogrel is considered safe. If the patient is to undergo hip fracture repair in this time window, both antiplatelet agents should ideally be continued, provided that the increased risk of bleeding is acceptable to the patient and the surgical team. If clopidogrel therapy is interrupted in a patient with a cardiac stent, the time without dual antiplatelet inhibition should be minimized. A loading dose of 300 to 600 mg of clopidogrel postoperatively will achieve maximum platelet inhibition in less than 24 hours (compared with 5 to 10 days with 75 mg daily dosing). 55

Summary
Patients with an acute hip fracture present a challenge to the care team. This patient population has considerable perioperative morbidity and mortality. However, there is little time to make a significant impact on the underlying status of these patients because delay of surgical repair past 48 hours may increase the risk of complications. Stratification of patients’ underlying cardiac risk with the RCRI helps in planning postoperative care and guides appropriate preoperative assessment. The medical consultant should perform a thorough but rapid assessment of patients at increased perioperative cardiac risk. Optimization should be limited to interventions that have been shown to affect patients’ perioperative outcomes favorably. Management of severe physiologic derangements and of unstable cardiac conditions should take priority. The likelihood of a smooth postoperative course for these patients is maximized by careful assessment, prevention of predictable complications (delirium, VTE), and management of complex drug regimens including anticoagulants, antiplatelet agents, and cardiac medications.

References

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31 POISE study group. Effects of extended-release metoprolol succinate in patients undergoing non-cardiac surgery (POISE trial): a randomised controlled trial. Lancet . 2008;371:1839-1847.
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33 Lindenauer P.K., Pekow P., Wang K., et al. Lipid lowering therapy and in-hospital mortality following major noncardiac surgery. JAMA . 2004;291:2092-2099.
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37 Cummings S.R., Kelsey J.L., Nevitt M.C., et al. Epidemiology of osteoporosis and osteoporotic fractures. Epidemiol Rev . 1985;7:178-207.
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39 Lawrence V.A., Hilsenbeck S.G., Noveck H., et al. Medical complications and outcomes after hip fracture repair. Arch Intern Med . 2002;162:2053-2057.
40 Smetana G.W. Preoperative pulmonary evaluation. Cleve Clin J Med . 2006;73:S36-S41.
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42 Hoogwerf B.J. Perioperative management of diabetes mellitus: how should we act on the limited evidence? Cleve Clin J Med . 2006;73:S95-S99.
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44 Cohen S.M., Te H.S., Levitsky J. Operative risk of total hip and knee arthroplasty in cirrhotic patients. J Arthroplasty . 2005;20:460-466.
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46 Moon Y.W., Kim Y.S., Kwon S.Y. Perioperative risk of hip arthroplasty in patients with cirrhotic liver disease. J Korean Med Sci . 2007;22:223-226.
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48 Schreiber M.J. Minimizing perioperative complications in patients with renal insufficiency. Cleve Clin J Med . 2006;73:S116-S120.
49 Kalisvaart K.J., Vreeswijk R., de Jonghe J.F.M., et al. Risk factors and prediction of postoperative delirium in elderly hip-surgery patients: implementation and validation of a medical risk factor model. J Am Geriatr Soc . 2006;54:817-822.
50 Marcantonio E.R., Goldman L., Mangione C.M., et al. A clinical prediction rule for delirium after elective noncardiac surgery. JAMA . 1994;271(2):134-139.
51 Palmer R.M. Perioperative care of the elderly patient. Cleve Clin J Med . 2006;73:S106-S110.
52 Kalisvaart K.J., De Jonghe J.F.M., Bogaards M.J., et al. Haloperidol prophylaxis for elderly hip-surgery patients at risk for delirium: a randomized placebo-controlled study. J Am Geriatr Soc . 2005;53:1658-1666.
53 Becker R.C. The importance of VTE prevention after orthopaedic surgery. Lancet . 2009;373:1661-1662.
54 Turpie A.G.G., Lassen M.R., Davidson B.L., et al. Rivaroxaban versus enoxaparin for thromboprophylaxis after total knee arthroplasty (RECORD 4): a randomised trial. Lancet . 2009;373:1673-1680.
55 Douketis J.D., Berger P.B., Dunn A.S., et al. The perioperative management of antithrombotic therapy. Chest . 2008;133:299S-339S.
Section III
Anesthesia and Pain Management
4 Regional versus General Anesthesia for Fractures of the Proximal Femur

Tania Di Renna, Aaron Hong

General Anesthesia 43
Preoperative Preparation 43
Technique 44
Benefits 44
Risks 44
Regional Anesthesia 45
Options 45
Techniques 45
Benefits 46
Contraindications 46
Risks 46
Special Considerations 47
Postoperative Cognitive Dysfunction 47
Time and Cost Issues 47
Summary 47
Anesthesia is commonly classified into two main techniques: general anesthesia, in which inhalational agents or intravenous drugs produce central nervous system depression; and regional anesthesia, in which drugs are administered directly to the spinal cord or nerves to block afferent and efferent nerve input locally. 1 The selection of one of these techniques for the repair of fractures of the proximal femur depends on certain factors, including the patient’s comorbidities, the overall requirements of the surgical procedure, and the postoperative analgesic requirements.
Anesthesia for proximal femur fracture repair presents a challenge because patients are typically elderly and may have significant comorbid conditions, such as ischemic heart disease, hypertension, renal dysfunction, chronic obstructive pulmonary disease (COPD), diabetes, and obesity, all of which can adversely affect patient management in the perioperative period. It is therefore important to choose an effective anesthetic technique that the patient will tolerate with minimal side effects. The anesthetic technique must also allow optimal functional recovery and decrease postoperative morbidity and mortality. Despite the large number of proximal femur fracture repairs performed, an evidence-based international consensus on anesthetic technique does not exist. Anesthetic management tends to be influenced at an institutional level by factors such as local experience and skills.

General Anesthesia
General anesthesia involves rendering a patient unconscious by using intravenous medications, inhalational agents, or a combination. For general anesthesia to be safe and adequate, the anesthesiologist must address the combined needs for unconsciousness, analgesia, and muscle relaxation in the patient to provide the best operative conditions for the surgeon.
Administering a general anesthetic regimen encompasses several stages, including preoperative preparation, premedication, induction, maintenance, extubation, postoperative care, and postoperative pain management.

Preoperative Preparation
Ideally, preparation for anesthesia should be preformed well in advance of the surgery date. Preoperative preparation involves obtaining a targeted history, performing a focused physical examination, ordering and reviewing investigations, and optimizing the patient for surgery. The anesthesiologist will look for specific factors that may cause a patient to be a better candidate for general or neuraxial anesthesia.
The targeted anesthetic history includes the history of presenting illness, medications, allergies, previous anesthetics, family history of malignant hyperthermia, and past medical history. Important comorbidities that may affect candidacy for surgery and choice of anesthesia are sought, including the presence of cardiac dysfunction (coronary artery disease, valvulopathy), respiratory illness (COPD, asthma), bleeding diathesis (von Willebrand’s disease, hemophilia), diabetes, and acid reflux.
The focused physical examination includes an airway examination that will determine the patient’s ease of intubation, identification and inspection of potential regional landmarks for neuraxial techniques, and a cardiorespiratory assessment. Laboratory investigations may include an electrocardiogram, a complete blood count, electrolyte determinations, coagulation studies, or other more involved studies, depending on the disorders elicited during the history and physical examination.
Preoperative optimization may be required if the patient is taking anticoagulant medication, insulin, or oral hypoglycemic agents or has poorly controlled comorbidities. For example, a patient with poorly controlled COPD may need a course of antibiotics, corticosteroids, bronchodilators, and a respirology assessment before general anesthesia can be considered. Optimization may also include stopping anticoagulants, reversing an elevated international normalized ratio (INR), discontinuation of oral hypoglycemic agents the evening before the surgical procedure, initiating antihypertensive medications, and obtaining consultations from other services or specialists to help with comorbidity management or simply to obtain a risk assessment. For fractures of the proximal femur, the Royal College of Physicians’ guidelines recommend surgical repair within 24 hours after hospital admission; however, the effect of operative delay on mortality remains controversial. According to one study, operative delay beyond 48 hours after admission may increase the odds of 30-day all-cause mortality by 41% and of 1-year all-cause mortality by 32%. 2

Technique
The first phase of administering general anesthesia starts with premedication, which can include anxiolytics, antibiotics, bronchodilators, antisialagogues, and antireflux medications. Induction is one of the most important stages of anesthesia because the patient transitions from the awake to the unconscious state. Induction of anesthesia can be achieved with intravenous medications or inhalational agents. Medications given intravenously include the following: benzodiazepines, which reduce anxiety and cause amnesia; opioids, which are used for both analgesia and suppression of the sympathetic response to intubation; the induction agent (propofol, thiopental); and the muscle relaxant, which relaxes the oropharyngeal muscles to allow the passage of an endotracheal tube (ETT) through the vocal cords. The specific combination of these drugs depends on the patient’s characteristics and the anesthesiologist’s preference. The dose of medication may be precalculated based on weight or titrated to effect. Muscle relaxation given during induction or repeated doses of muscle relaxants given throughout the operation may provide optimal operating conditions; however, caution is exercised with muscle relaxation near the end of a procedure because it may prolong extubation time.
Rendering a patient unconscious requires airway protection in the form of an ETT or a laryngeal mask airway (LMA) because induction of anesthesia results in the loss of protective airway reflexes. The ETT or LMA allows the delivery of oxygen and inhalational agents for maintenance of anesthesia. Maintenance can usually be achieved with inhalational agents, continuous intravenous infusions, or a combination. Analgesic medications can be given in the form of long-acting opioids, frequent doses of shorter-acting opioids, or continuous infusions.
Once the surgical procedure is complete, muscle relaxants are generally reversed, and inhalational agents or intravenous anesthestics are discontinued. Most nondepolarizing muscle relaxants can be reversed only if they have already begun to wear off. Only when patients are breathing spontaneously, maintaining adequate respiratory parameters, obeying commands, and displaying adequate strength to maintain airway reflexes should they be extubated. Patients are then usually monitored for a brief period in the postanesthesia care unit after the surgical procedure. Patients must meet certain institutional criteria before they are discharged to the ward or home. Certain patients, such as those with sleep apnea or a personal history of malignant hyperthermia, may require a prolonged hospital stay to monitor for respiratory depression or a malignant hyperthermia crisis, respectively. Patients who do not meet criteria for extubation or those with significant comorbidities that put them at higher risk for postoperative morbidity and mortality may require postoperative monitoring in a more intensive setting. After receiving general anesthesia, patients may be given a patient-controlled analgesia (PCA) pump, in which a preset amount of narcotic is given by the intravenous route at set intervals on demand.

Benefits
The patient’s preference is a reasonable indication for general anesthesia unless comorbid conditions preclude the delivery of a safe anesthetic regimen. General anesthesia is considered safer than neuraxial anesthesia in patients with fixed cardiac output states such as aortic stenosis. General anesthesia is also considered prudent in patients with massive hemorrhage or hemodynamic instability and is safer than regional anesthesia in coagulopathic patients or those who have had a recent intake of low-molecular-weight heparin (LMWH).

Risks
No single contraindication to general anesthesia exists. Certain patients may be at higher risk for not tolerating intubation and ventilation (i.e., severe COPD), whereas others may not tolerate the hemodynamic changes induced by anesthetic agents. Death secondary to anesthesia alone occurs in less than 1 in 10,000 patients (average figures incorporating both elective and emergency patients and including all comorbidities). 3 Postoperative nausea and vomiting, drowsiness, and sore throat occur at rates of 5%, 15%, and 25%, respectively. 3

Regional Anesthesia

Options
For the purpose of repairing proximal femur fractures, the two most common neuraxial techniques used are spinal (intrathecal) anesthesia and epidural anesthesia. A spinal anesthetic regimen is a single-shot technique that involves injecting a combination of local anesthetics and opioids into the subarachnoid space. An epidural anesthetic regimen can be administered either as a single shot or usually as a continuous technique that allows an infusion of local anesthetics and opioids into the epidural space. These techniques can also be combined, as in combined spinal epidural (CSE) anesthesia.
The differences between spinal and epidural techniques include the onset of action, which is faster in spinal anesthesia. The time to achieve maximal cephalad spread is approximately 10 to 13 minutes, whereas it averages 20 minutes with an epidural anesthetic. 4 Another difference is the degree of motor blockade, which is more intense when a spinal anesthetic is used and can theoretically improve operating conditions. An epidural anesthetic can allow for a more gradual onset, which is beneficial in patients who cannot tolerate abrupt changes in hemodynamics. It can also be used for postoperative analgesia. The duration of epidural infusion depends on several factors. Epidural catheters must be removed before the advent of significant anticoagulation from heparin, LMWH, or warfarin. Epidural catheters are generally removed by 72 hours to reduce the risk bacterial colonization at the catheter site. 5
The rationale for choosing one regional anesthetic technique over the other depends on the patient’s characteristics and the surgical procedure. If abrupt changes in hemodynamics will pose a threat or if postoperative pain control may be challenging, then an epidural anesthetic is most suitable. Long-acting opioids can be used in spinal anesthesia and, in the case of morphine, can provide anywhere from 18 to 24 hours of pain relief, depending on the dose used. 6 When the duration of the surgical procedure is expected to be prolonged, then a continuous technique such as an epidural anesthetic or a CSE regimen is preferable. The advantages of spinal analgesia over epidural anesthesia include its simplicity, the lack of need for catheter care or pumps, its low cost, and easy supplementation with low-dose PCA narcotics as needed. The main disadvantage of this technique is its limited duration of action in comparison with catheter techniques.

Techniques
The patient can be positioned in the sitting or lateral decubitus position with the spine maximally flexed, to enlarge the distance between the spinous processes. The patient is cleaned with iodine or chlorhexidine solution, and the surgical site is prepared in sterile fashion. As a landmark, the L4 spinous process can be marked by a horizontal line running between the superior aspects of the iliac crests (Tuffier’s line). Local anesthetic is infiltrated into the skin and surrounding tissue. The techniques are then different for spinal and epidural blocks.
For spinal anesthesia using the midline approach, a 22- to 27-gauge needle is inserted with a slight cranial angulation between the lumbar spinous processes ( Fig. 4-1 ). The needle passes through subcutaneous tissue, the supraspinous and interspinous ligaments, and the ligamentum flavum, is then advanced through the dura and arachnoid mater, and finally enters the subarachnoid space. This placement can be confirmed by the presence of cerebrospinal fluid. Local anesthetic with or without opioid is deposited into the subarachnoid space.

Figure 4-1 Spinal anesthetic.
(Courtesy of Dr. Bok Man Chan.)
For epidural anesthesia, the “loss of resistance” technique is a common method of epidural cannulation.

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