CLINICS IN SPORTS MEDICINE

Transcription

1 CLINICS IN SPORTS MEDICINE Stress Fractures CONTENTS VOLUME 25 NUMBER 1 JANUARY 2006 Foreword xiii Mark D. Miller Preface Christopher C. Kaeding xv The Pathophysiology of Stress Fractures 1 Michelle Pepper, Venu Akuthota, and Eric C. McCarty Stress fractures can occur in any active individual, from the weekend warrior to the elite athlete. As these injuries occur, it is important to understand how bones respond to the stresses placed on them. The understanding of potential intrinsic and extrinsic causes is important in treatment of these injuries. The proper identification and prevention of these stress injuries allows for athletes to return to activity expeditiously. Classification and Return-to-Play Considerations for Stress Fractures 17 Jason J. Diehl, Thomas M. Best, and Christopher C. Kaeding Stress fractures are common injuries, particularly in endurance athletes. Stress fracture management should take into consideration the injury site (low risk versus high risk), the grade (extent of microdamage accumulation), and the individual s competitive situation. The authors briefly discuss the pathophysiology and diagnostic process of stress fractures and expand on the classification of stress fractures and its impact on returnto-play decision making based on the relative risk of the fracture. Treatment of Stress Fractures: The Fundamentals 29 William Glenn Raasch and David J. Hergan This article is an introduction to the fundamentals of stress fracture management. Extrinsic and intrinsic factors, that may play a role in the development of stress fractures, are discussed and incorporated as possible treatment options. Different treatment modalities including ultrasound and electromagnetic fields are addressed, with an emphasis on literature support. vii

2 Epidemiology of Stress Fractures 37 Rebecca A. Snyder, Michael C. Koester, and Warren R. Dunn Stress fractures are a frequent cause of injury in competitive and recreational athletes. Although a number of epidemiologic studies have been conducted, the populations studied and data collection methods have varied. This article presents an overview of injury epidemiology and reviews the current body of literature regarding the occurrence of stress fractures in athletes. Given the heterogeneity of the populations studied and the variations in data collection, few broad conclusions can be drawn. There is a pressing need for large prospective studies to better establish the risks of stress fracture by sport, age, and gender. Imaging of Stress Fractures 53 Carolyn M. Sofka The imaging evaluation of a patient who has a clinically suspected stress reaction or fracture should begin with high-resolution radiographs of the area in question. In inconclusive or indeterminate cases, additional imaging should be obtained. CT provides exquisitely fine osseous detail, in multiple planes, often demonstrating the endosteal remodeling or fracture line that is not apparent on conventional radiographs. The sensitivity of nuclear scintigraphy depicts areas of even subtle osseous turnover and stress remodeling. Ultrasonography, used increasingly in the evaluation of the musculoskeletal system, can provide a limited evaluation of the superficial osseous structures, providing an imaging alternative, especially in patients who are MRI-incompatible. MRI, however, provides the most comprehensive evaluation of stress injuries, revealing both functional and morphologic information about the bone. Pharmacologic Agents in Fracture Healing 63 Michael C. Koester and Kurt P. Spindler Bone fractures are a known risk of athletic participation and can result in significant lost playing time. A variety of medications have been investigated in animal studies regarding their effects on fracture healing. Parathyroid hormone and the bisphosphonates may have future uses in the prevention and treatment of athletic-related stress fractures and acute fractures. Nonsteroidal anti-inflammatory drugs have been implicated in effecting fracture healing in some animal models, but little clinical evidence supports these findings. Large randomized clinical trials are needed to further delineate the role of these and other drugs and their effects on fracture healing. viii

3 Stress Fractures in the Spine and Sacrum 75 Lyle J. Micheli and Christine Curtis Stress fractures of the pars, pedicle, and sacrum are important considerations in the differential diagnosis of lower back pain in the child or adolescent athlete. A thorough history and physical examination as well as a high index of suspicion are essential when assessing a patient with lower back pain. Diagnostic imaging, including radiographs, bone scans, CT scans, and other imaging modalities are important for further narrowing the diagnosis. The early identification and proper management of stress fractures of the pars, pedicle, and sacrum are integral in the prevention of stress fractures in the adolescent athlete population. This article reviews current concepts in the assessment and management of stress fractures of the lumbosacral spine, particularly of the pars (spondylolysis), pedicles, and sacrum. Stress Fractures of the Femur in Athletes 89 Michael J. DeFranco, Michael Recht, Jean Schils, and Richard D. Parker Femoral stress fractures represent an uncommon but important lowerextremity injury in athletes and soldiers. Careful assessment of the involved and contralateral lower extremity and the spine is required to make the diagnosis. Based on a review of the literature, specific treatment is based on individual patient assessment. In most cases, nonoperative management results in an excellent outcome. Certain fractures will require operative intervention to prevent displacement or to reduce a displaced fracture and return stability to the lower extremity. Complications in athletes with femoral stress fractures are rare. Most athletes can expect to return to their preinjury level of competition, if they are compliant with the treatment plan. Stress Fractures Around the Knee 105 Raymond R. Drabicki, William J. Greer, and Patrick J. DeMeo Stress fractures of the lower extremities are common, especially in the younger athletic population. The current literature consists of mainly a variety of case reports but is devoid of any sizeable series of knee stress fracture investigations. Diagnosing a stress fracture around the knee can be a challenge. The proximity of the stress fracture to the knee joint may lead the clinician to investigate intra-articular or other periarticular pathology. The differential diagnosis can be large, including bursitis, tendonitis, mechanical causes, insufficiency fracture, and tumor. A high index of suspicion is necessary to confirm the underlying diagnosis. A patient s medical history combined with a physical examination and imaging modalities will aid the physician in arriving at the diagnosis of stress fracture. ix

4 Evaluation and Treatment of Tibial Stress Fractures 117 Andrea J. Young and David R. McAllister Tibial stress fractures are relatively common overuse injuries that can often be difficult to treat. Other comorbid medical conditions, including the female athlete triad, need to be carefully evaluated and treated. Nonoperative treatment is the standard, but surgical intervention may be necessary. Intramedullary nailing may allow return to sport but does not guarantee healing. Stress Fractures of the Medial Malleolus and Distal Fibula 129 Paul S. Sherbondy and Wayne J. Sebastianelli Stress fractures of the medial malleolus and distal fibula are rarely encountered. They typically affect the athletic and running population and manifest the usual signs and symptoms of stress fractures. Axial and torsional forces, muscular contractions, and alignment are believed to play a role in their development. Plain radiographs are often initially nondiagnostic. The diagnosis can be confirmed with radionuclide bone scanning or MRI. Most injuries are amenable to nonsurgical management. An operative intervention for athletes with medial malleolar stress fractures has been advocated under certain circumstances. Metatarsal Shaft Fractures and Fractures of the Proximal Fifth Metatarsal 139 Gary B. Fetzer and Rick W. Wright Metatarsal fractures represent a relatively common injury, especially in athletes. The pertinent anatomy, evaluation, diagnosis, classification, and treatment of acute and chronic (stress) metatarsal shaft fractures are discussed. Fractures of the proximal fifth metatarsal, which are unique and important injuries, are also discussed. Treatment remains relatively straightforward for the traumatic metatarsal injury, whereas traditional stress fractures typically heal with decreased activity. The problematic proximal fifth metatarsal fracture ( Jones fracture) frequently requires surgical intervention in patients who want to avoid non weight-bearing cast immobilization. The authors current treatment for this fracture includes the option of intramedullary fixation versus cast immobilization. Navicular Stress Fractures 151 Morgan H. Jones and Annunziato S. Amendola Since the stress fracture of the tarsal navicular was first described in 1970, awareness of the injury has increased, and navicular stress fractures have represented up to 35% of stress fractures in recent series. x

5 However, these injuries remain difficult to diagnose and treat because of their often vague clinical presentation and the poor correlation between radiographic and clinical findings. Upper Extremity Stress Fractures 159 Grant Lloyd Jones Although less common than lower-extremity stress fractures, upperextremity stress fractures are becoming recognized much more frequently. A majority of these fractures are caused by overuse and fatigue of the surrounding musculature and, as a result, may be prevented by appropriate training and conditioning. Diagnosis is made by history and physical examination with the aid of plain radiographs, bone scans, and MRI. Most of these fractures heal with a period of relative rest followed by a structured rehabilitation program. A small percentage of these fractures, however, may require surgical fixation. The present article reviews the different types of upper extremity and torso stress fractures seen in athletes, starting with the sternum and extending outward to the fingers. The presentation, diagnosis, mechanism of injury, treatment, prevention, and prognosis for each of these injuries will be discussed. Index 175 xi