Arthroplasty in the treatment of subcapital hip fracture.

After reviewing recent literature on the treatment of displaced intracapsular fractures of the femoral neck (Garden types III and IV) and from personal experience, a number of conclusions can be made. Orthopedic surgeons and hospitals face the challenge of providing the treatment most beneficial to patients with intracapsular, subcapital hip fractures in the most cost-effective way. The numbers of patients will increase annually and exceed the 125,000 per year at present in the United States. Most authors agree that fractures with the least displacement and younger, more demanding patients will do well with a precise fracture reduction without delay and an accurately placed internal fixation system. However, an overall median risk for reoperation 2 years after internal fixation is 35%. A patient with a displaced intracapsular fracture will need to consider monopolar, bipolar, or THA as the treatment of choice. Monopolar and bipolar arthroplasty have a reduced survivorship compared to THA and are not as suitable for the younger, more active patient. A large femoral head implant leads to decreased motion from increased friction and an undersized head implant leads to reduced contact area with increased erosion and pain. Bipolar arthroplasties, while allowing early mobilization, may develop some of the characteristics of monopolar implants if motion is not mainly at the internal joint. The increased cost may not justify their use over monopolar arthroplasty. Should dislocation occur, monopolar implants are easier to reduce (closed) than bipolar. Ceramic heads on monopolar or bipolar arthroplasties offer reduced wear and less erosion of the acetabulum. Total hip arthroplasty provides early mobilization, long-term pain relief, and little additional morbidity at surgery. The increased rate of early dislocation may be related to surgeon skill rather than an inherent failure of the system. If the early dislocators are removed from consideration, the complication rate drops to equal that of monopolar and bipolar implants. Total hip arthroplasty also is cost effective. Total hip arthroplasty may be the only option if pre-existing arthritis, significant osteoporosis, or Paget's disease of the pelvis is present.