Cemented Bipolar Hemiarthroplasty Provides Definitive Treatment for Femoral Neck Fractures at 20 Years and Beyond.

backgroundDisplaced femoral neck fractures frequently are treated with bipolar hemiarthroplasties. Despite the frequency with which bipolar hemiarthroplasty is used to treat these fractures, there are few long-term data. QUESTIONS/PURPOSES: We sought to evaluate (1) the cumulative incidence of revision for any reason of bipolar hemiarthroplasties at 20 years, and the proportion of patients who lived more than 20 years who still have the prosthesis in situ from the index arthroplasty, (2) the cumulative incidence of aseptic loosening at 20 years, and (3) the Harris hip score of the surviving patients at long term.

methodsWe performed 376 cemented bipolar hemiarthroplasties for displaced femoral neck fractures in 359 patients between 1976 and 1985. At a minimum of followup of 20 years (mean, 24 years; range, 20-31 years), 339 of 359 patients (94%) were deceased, leaving 20 patients in the study group. Of those, one patient was confirmed to be lost to followup and two others had radiographic followup only. Three hundred fifty-nine patients (99.2%) (376 of the original 379 hips) were followed until death, revision of the hemiarthroplasty, or for at least 20 years (of clinical followup). Bipolar hemiarthroplasty was performed for displaced femoral neck fractures. Cemented fixation was the standard of care between 1976 and 1985 at our institution. The mean age of the patients at the time of surgery was 79 years (range, 60-99 years). The cumulative incidence of revision, estimated with death as a competing risk, and radiographs were evaluated for signs of aseptic loosening by a surgeon not involved in the clinical care of the patients. Clinical function was evaluated with the Harris hip score. The mean age of the patients at the time of surgery was 79 years.

resultsThe 20-year cumulative incidence of revision for any reason was 3.5% (95% CI, 1.6%-5.3%). Of the 20 patients who survived more than 20 years, seven had the implant intact. The 20-year cumulative incidence of revision for aseptic loosening was 1.4% (95% CI, 0.2%-2.6%). The mean Harris hip score in patients who were still living and patient who did not have revision surgery was 63 ± 22, however 13 of the 20 patients had undergone revision surgery.

conclusionsThe long-term survivorship of bipolar hemiarthroplasty prostheses used to treat displaced femoral neck fractures in the elderly was high, and the procedure can be considered definitive for the majority of elderly patients with a femoral neck fracture. In this series, 6% (20 patients, 339 of 359) of the patients survived more than 20 years after treatment of a femoral neck fracture with a bipolar hemiarthroplasty. Of those, 35% (seven of 20) survived with their index prosthesis in situ. LEVEL OF EVIDENCE: Level IV, therapeutic study.