Background: Arthroplasty has been shown to be superior regarding low risk of reoperation and better function score to internal fixation for treatment of displaced femoral neck fractures at short-term followup. However, there are unanswered questions regarding the efficacy of arthroplasty in the longer term compared with internal fixation.
Questions/purposes: We performed a meta-analysis comparing arthroplasty (hemiarthroplasty or THA) with internal fixation in patients with displaced femoral neck fractures with respect to (1) mortality, (2) reoperation, (3) functional recovery, and (4) complications, including only randomized trials with a minimum of 4 years followup.
Methods: Computerized databases, including PubMed (MEDLINE), EMBASE, Cochrane Register of Controlled Trials databases, and Web of Science™ were searched for studies published from the inception date for each database to March 2014. Eleven randomized controlled trials that compared arthroplasty (either hemiarthroplasty or THA) with internal fixation for treatment of patients with a femoral neck fracture were included in our analysis. The quality of the trials was assessed according to the Cochrane Handbook and meta-analyses were conducted using RevMan 5.2 software from the Cochrane Collaboration. The heterogeneity among studies was evaluated by the I-squared index (I2) and publication bias was assessed using forest plots.
Results: There were no differences between the internal fixation and arthroplasty groups for patient mortality at mid-term (48.4% vs 46.8%) or long-term followup (83.2% vs 81.5%). Arthroplasty was associated with a lower risk of reoperation at mid-term (7.2% vs 39.8%; relative risk [RR]=0.10; 95% CI, 0.06-0.07) and at long-term followup (14.3% vs 43.8%; RR=0.10; 95% CI, 0.06-0.07). Arthroplasty was associated with better functional recovery at mid-term followup (standard mean difference [SMD]=0.55; 95% CI, 0.02-1.09), whereas function at long-term followup (SMD=0.14; 95% CI, -0.35 to 0.62) was not different between the arthroplasty and internal fixation groups. There were no significant differences in subsequent ipsilateral fractures (1.5% vs 1.2%; RR=2.18; 95% CI, 0.32-14.67; p=0.42) and deep infections (2.7% vs 2.9%; RR=0.89; 95% CI, 0.40-2.01; p=0.78) between patients treated with arthroplasty and internal fixation.
Conclusions: Based on our results, we found that compared with internal fixation, arthroplasty may result in a lower rate of subsequent reoperation at mid- and long-term followup, and better mid-term functional recovery. Future studies should investigate the mid- and long-term results of THAs compared with hemiarthroplasty.