Comparison of complications between total hip arthroplasty following failed internal fixation and primary total hip arthroplasty for femoral neck fractures: A meta-analysis

Objectives: In this meta-analysis, we discuss the complication rates of conversion to total hip arthroplasty (cTHA) following failed internal fixation (IF) of femoral neck fractures (FNFs) versus primary total hip arthroplasty (pTHA). Materials and methods: The Cochrane Library, Web of Science, PubMed, Embase, and Science Direct databases were searched for eligible publications published prior to December 2024. The search terms included "femoral neck fracture", "internal fixation failure", and "total hip arthroplasty". The mean difference (MD) and risk difference (RD) were used as combined variables, and 95% confidence intervals (CIs) were chosen. Results: Six non-randomized-controlled clinical trials comprising 1,301 patients were included in this meta-analysis. The pooled data revealed statistically significant differences in postoperative deep infection rates (RD=0.04; 95% CI: 0.01-0.08; p=0.009), periprosthetic fractures (RD=0.03; 95% CI: 0.00-0.05; p=0.03), and reoperation rates (RD=0.07; 95% CI: 0.03-0.11; p=0.0002) between the cTHA and pTHA groups. However, no significant differences were observed in the incidence of postoperative dislocations (RD=0.05; 95% CI: -0.03-0.13; p=0.19), deep vein thrombosis (RD= -0.01; 95% CI: -0.04-0.03; p=0.77), superficial infections (RD=0.02; 95% CI: -0.02-0.06; p=0.37), or revision surgeries (RD=0.02; 95% CI: -0.01-0.05; p=0.13). Conclusion: Compared to pTHA, cTHA following failed IF of FNFs was associated with higher deep infection, periprosthetic fractures, and reoperation rates.