Association between hospital surgical volume and complications after total hip arthroplasty in femoral neck fracture: A propensity score-matched cohort study

Abstract

Background: For displaced femoral neck fractures (FNF), total hip arthroplasty (THA) or hemiarthroplasty (HA) is preferred rather than fracture fixation. THA for patients with FNF requires skilled operators since patient with FNF likely to have osteoporosis and a higher risk of complications. Several reports suggest that higher hospital surgical volume was associated with a lower risk of complications after THA for osteoarthritis. However, little is known concerning this association with THA for FNF. Herein, we investigated the association between THA and complication and the recovery of physical function after THA to optimize the quality of FNF.

Methods: A nationwide retrospective cohort study of elderly undergoing THA between April 1, 2011, to March 31, 2018 was performed. The association between hospital surgical volume and complication after THA for FNF was visually described with the restricted cubic spline regression analysis. Then the risk of complications was quantified with propensity score matching analysis based on the cutoff point identified by the restricted cubic spline curve. Primary outcome was secondary revision surgery, and the secondary outcomes included surgical and systemic complications, and the recovery of physical function at hospital discharge.

Results: By visualization of the spline curve, we identified 20 cases per year as cutoff point of low hospital surgical volume. Following 1,396 patients' propensity score-match analysis (mean age 75.2 [SD] 8.8, female 80.4%), the risk of secondary revision surgery was significantly higher among the low hospital surgical volume group (absolute risk difference (RD), 2.44%; p = 0.011). Also, the incidence of blood transfusion was higher in the low hospital surgical volume group (RD, 4.01%; p = 0.049). However, there was no significant difference in the recovery of the transferring and walking ability at discharge between high and low hospital surgical volume groups (63.5% vs 62.6%, 58.5% vs 57.5%; p = 0.74, 0.71, respectively).

Conclusion: Our research demonstrated that an increase in hospital surgical volume significantly reduced the incidence of secondary revision surgery after a certain inflection point, but not significantly improved short-term physical functions.

Keywords: Complication; Femoral neck fracture; Hip Fracture; Hospital volume; Total Hip Arthroplasty.