Primary Total Hip Arthroplasty for Displaced Femoral Neck Fracture

Fracture of the femoral neck is a common injury, especially in the elderly. Currently, approximately $8.7 billion is spent treating 250,000 femoral neck fractures per year, which indicates that the 500,000 projected to occur annually by 2040 will have a staggering economic impact. The optimal treatment for displaced femoral neck fractures in healthy elderly patients has been controversial. Recent literature supports total hip arthroplasty (THA) as the preferred method, citing equivalent mortality, reduced complication rate, and better functional scores than both fracture reduction and fixation and hemiarthroplasty. The fixation group, which was initially less expensive, had a reoperation rate of 39%, while the arthroplasty group's rate was only 9%. Total hip arthroplasty for displaced femoral neck fracture has potential advantages over open reduction and internal fixation and hemiarthroplasty. Thirty-seven patients who underwent THA for displaced femoral neck fractures between June 1993 and June 2005 were evaluated. The exact head/neck ratios were calculated by the prosthesis manufacturers. The major complication rate was 16.1% (6 of 37) with 5 dislocations (all with surgery prior to 2002) and one nonfatal myocardial infarction. One-and 2-year mortality was 2.7% (1 of 37) and 8.1% (3 of 37), respectively. A smaller head/neck ratio (P=.002) in patients who dislocated was observed. The optimal head/neck ratio was >= 2.13. Total hip arthroplasty for displaced femoral neck fracture allows patients to return to most preinjury activities. In order to avoid dislocation, constructs with a larger head/neck ratio should be used.