Screw Fixation Versus Hemiarthroplasty for Nondisplaced Femoral Neck Fractures in Elderly Patients: A Multicenter Randomized Controlled Trial.

BACKGROUND

Elderly patients with a displaced femoral neck fracture treated with hip arthroplasty may have better function than those treated with internal fixation. We hypothesized that hemiarthroplasty would be superior to screw fixation with regard to hip function, mobility, pain, quality of life, and the risk of a reoperation in elderly patients with a nondisplaced femoral neck fracture.

METHODS

In a multicenter randomized controlled trial (RCT), Norwegian patients ≥70 years of age with a nondisplaced (valgus impacted or truly nondisplaced) femoral neck fracture were allocated to screw fixation or hemiarthroplasty. Assessors blinded to the type of treatment evaluated hip function with the Harris hip score (HHS) as the primary outcome as well as on the basis of mobility assessed with the timed "Up & Go" (TUG) test, pain as assessed on a numerical rating scale, and quality of life as assessed with the EuroQol-5 Dimension-3 Level (EQ-5D) at 3, 12, and 24 months postsurgery. Results, including reoperations, were assessed with intention-to-treat analysis.

RESULTS

Between February 6, 2012, and February 6, 2015, 111 patients were allocated to screw fixation and 108, to hemiarthroplasty. At the time of follow-up, there was no significant difference in hip function between the screw fixation and hemiarthroplasty groups, with a 24-month HHS (and standard deviation) of 74 ± 19 and 76 ± 17, respectively, and an adjusted mean difference of -2 (95% confidence interval [CI] = -6 to 3; p = 0.499). Patients allocated to hemiarthroplasty were more mobile than those allocated to screw fixation (24-month TUG = 16.6 ± 9.5 versus 20.4 ± 12.8 seconds; adjusted mean difference = 6.2 seconds [95% CI = 1.9 to 10.5 seconds]; p = 0.004). Furthermore, screw fixation was a risk factor for a major reoperation, which was performed in 20% (22) of 110 patients who underwent screw fixation versus 5% (5) of 108 who underwent hemiarthroplasty (relative risk reduction [RRR] = 3.3 [95% CI = 0.7 to 10.0]; number needed to harm [NNH] = 6.5; p = 0.002). The 24-month mortality rate was 36% (40 of 111) for patients allocated to internal fixation and 26% (28 of 108) for those allocated to hemiarthroplasty (RRR = 0.4 [95% CI = -0.1 to 1.1]; p = 0.11). Two patients were lost to follow-up.

CONCLUSIONS

In this multicenter RCT, hemiarthroplasty was not found to be superior to screw fixation in reestablishing hip function as measured by the HHS (the primary outcome). However, hemiarthroplasty led to improved mobility and fewer major reoperations. The findings suggest that certain elderly patients with a nondisplaced femoral neck fracture may benefit from being treated with a latest-generation hemiarthroplasty rather than screw fixation.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.