Total hip replacement versus open reduction and internal fixation of displaced femoral neck fractures: a randomized long-term follow-up study

Abstract

Background: Clinical trials with short and intermediate-term follow-up have demonstrated superior results for total hip replacement as compared with internal fixation with regard to hip function and the need for secondary surgery in elderly patients with a displaced intracapsular femoral neck fracture. The aim of the present study was to compare the results of total hip replacement with those of internal fixation over a long-term follow-up period of seventeen years.

Methods: We enrolled 100 patients who had sustained a femoral neck fracture in a single-center, randomized controlled trial;all patients had had a healthy hip before the injury. The study group included seventy-nine women and twenty-one men with a mean age of seventy-eight years (range, sixty-five to ninety years). The subjects were randomly assigned to either total hip replacement (the arthroplasty group) (n = 43) or internal fixation (the control group) (n = 57). The primary end point was hip function, evaluated with use of the Harris hip score. Secondary end points included mortality, reoperations, gait speed, and activities of daily life. Follow-up evaluations were performed at three months and at one, two, four, eleven, and seventeen years.

Results: The Harris hip score was higher in the total hip arthroplasty group, with a mean difference of 14.7 points (95%confidence interval, 9.2 to 20.1 points; p < 0.001 [analysis of covariance]) during the study period. We found no difference in mortality between the two groups. Four patients (9%) in the total hip replacement group and twenty-two patients (39%) in the internal fixation group had undergone a major reoperation (relative risk, 0.24; 95% confidence interval, 0.09 to 0.64).The overall reoperation rate was 23% (ten of forty-three) in the total hip replacement group and 53% (thirty of fifty-seven) in the internal fixation group (relative risk, 0.44; 95% confidence interval, 0.24 to 0.80). The results related to gait speed and activities of daily living favored the arthroplasty group during the first year.

Conclusions: Over a period of seventeen years in a group of healthy, elderly patients with a displaced femoral neck fracture, total hip replacement provided better hip function and significantly fewer reoperations compared with internal fixation without increasing mortality.

Level of evidence: Therapeutic Level I.