Hemiarthroplasty versus total hip arthroplasty for displaced femoral neck fractures: a meta-analysis of the literature

Background: Hemiarthroplasty and total hip arthroplasty are the two most common methods for displaced femoral neck fracture. However, the efficacy of the two methods is still controversial and needs a comprehensive analysis.

Objective: This meta-analysis was to investigate whether total hip arthroplasty (THA) is associated with lower reoperation rate, mortality, complications, better function and quality of life than hemiarthroplasty (HA) for patients with displaced femoral neck fractures.

Materials and Methods: Thirty-one trials involving a total of 4324 patients were included. Six randomized controlled trials, 8 lower-quality randomized trials, and 17 retrospective cohort studies comparing HA with THA for displaced femoral neck fractures were assessed for eligibility. Incidence rate and risk ratios (RR) were pooled using random-effects or fixed-effects models depending on the heterogeneity of included studies.

Results: Meta-analysis showed that THA was associated with a lower risk of reoperation (incidence rate 2.8%, 95%CI 1.8%-3.8%) compared with HA (incidence rate 7.4%, 95%CI 5.3%-9.6%) (RR = 0.42, 95%CI 0.30-0.58, P < 0.001) and higher excellent and good rate by Harris hip score (RR = 1.12, 95%CI 1.06-1.19, P < 0.001). There was a tendency of better prognosis in patients undergoing THA (RR_mortality = 0.82, 95%CI 0.67-1.01), but it was not statistically significant (P = 0.067). However, there was a higher risk of dislocation in patients undergoing THA (incidence rate 4.2%, 95%CI 2.7%-5.8%) compared with HA (incidence rate 2.3%, 95%CI 1.4%-3.2%) (RR = 1.79, 95%CI 1.24-2.57, P = 0.002), but there was no difference in both local infections and general complications (P = 0.201 and P = 0.712).

Conclusion: THA can benefit patients of displaced femoral neck fractures with a reduced reoperation rate and better hip function, though it can result a higher incidence of postoperative dislocation. The impact of different hip arthroplasty on prognosis need further studies.