Fractures of the Pelvis and Acetabulum

ractures of the hip joint include fractures of the proximal femur and acetabulum. Pelvic fractures also can be included in the category of hip fractures, because pain attributed to the hip region (ie, buttock, groin, thigh) can emanate from an injury to the pelvic ring. Hip fractures can affect both young and elderly populations. Usually, younger patients sustain pelvic or acetabular fractures as a result of significant trauma, whereas elderly patients can sustain such fractures as a result of more trivial events. A pathologic fracture can occur at any age but is most often seen with lowenergy injuries and may present with unusual fracture patterns. Whatever the etiology, however, hip fractures can lead to substantial morbidity and mortality. In younger patients, hip fractures generally are the result of high-energy events in which life-threatening injuries can occur. Initial orthopaedic concerns should focus on stabilizing the fracture to allow complete evaluation of the affected patient. Although pelvic and acetabular fractures in younger patients are often accompanied by other injuries, treatment of the fracture usually is emergent and often involves surgery. In contrast, in elderly patients, treatment of fractures of the pelvis and acetabulum is largely nonsurgical. Management of these injuries is more dependent on precise diagnostic evaluation, pain management, and rehabilitation. The medical, social, and economic issues that must be addressed in regard to elderly patients with pelvic and acetabular fractures extend beyond orthopaedic management and involve many different facets of the health care system. A previous article published in the April 2002 issue of Hospital Physician discussed fractures of the proximal femur. 1 This review focuses on the epidemiology, classification, and treatment of pelvic and acetabular fractures. Pathologic fractures related to primary or metastatic neoplasms require specialized evaluation and treatment and are beyond the scope of this article. EPIDEMIOLOGY AND EVALUATION OF PELVIC AND ACETABULAR FRACTURES High-Energy Fractures Pelvic and acetabular fractures can occur either with high-energy trauma or with low-energy or repetitive trauma. High-energy pelvic and acetabular fractures are rare. 2 Two-thirds of patients with this diagnosis also have other musculoskeletal injuries, 3 and more than half have multiple system injuries. 4 There is associated hemorrhage in 75% of cases, 5 urogenital injury in 12%, 6 and lumbosacral plexus injury in 8%. 5 In a large study reviewing the epidemiology of these fractures, pelvic ring injuries were classified as stable in 55% of cases, as rotationally unstable in 25%, and as unstable in translation in 21%; concomitant acetabular fractures were present in 16% of cases. 4 The rate of surgical fixation of high-energy fractures was examined in a study and varied by type 2 ; results showed that the least complex pelvic fractures are treated surgically less than 5% of the time, whereas the most complex are treated surgically more than half of the time. In isolated acetabular fractures, internal fixation was performed 39% of the time. 2 Total mortality after high-energy fractures is approximately 10%, with a 3-fold increase in patients with complex pelvic trauma, compared with patients without peripelvic injuries. 2,4,7 Risk factors for high-energy pelvic fractures are similar to those for blunt trauma in general (eg, motor vehicle use while under the influence of alcohol or drugs, driving with excessive speed, driving recklessly, not using seat belts when in an automobile, being in an automobile without air bags). The evaluation of a high-energy fracture of the pelvis or acetabulum requires a thorough medical history, physical examination, and radiographic studies. The best approach is to assess the patient in 2 stages with an interdisciplinary team, including a general surgeon, an emergency department physician, an anesthesiologist, and an orthopaedic surgeon. The first stage of the evaluation is an assessment of the affected patient for immediate F