Low Risk of Fracture Using a Cementless Triple-tapered Collared Femoral Stem with Automated Impaction in Direct...

Direct anterior approach (DAA) total hip arthroplasty (THA) has been associated with increased periprosthetic femoral fracture (PFF) risk. The aim of our study was to evaluate the fracture risk utilizing a triple tapered, collared stem with automated impaction through the anterior approach.

We retrospectively reviewed consecutive DAA THA procedures at a single institution performed by four experienced DAA THA surgeons between 2019 and 2021. We collected data on age, sex, body mass index, preoperative diagnosis, and intraoperative and early postoperative PFF within 6 weeks postoperatively. Preoperative radiographs were evaluated to determine femoral neck-shaft angle and Dorr classification. We used Wilcoxon Rank sum or Chi-square tests to assess differences between patients who did and did not have PFF. We also evaluated potential risk factors for PFF in unadjusted and adjusted regression analyses. In all, 24 PFFs (1.6%) occurred. There were eighteen fractures (1.2%) recognized and managed intraoperatively (15 calcar, 2 greater trochanter, 1 posterior cortical). There were six PFFs (0.4%) identified postoperatively (5 greater trochanter, 1 diaphyseal), of which 1 required a revision surgery.

Identified risk factors for fracture in adjusted regression models included women (Odds Ratio (OR)=2.76, P=0.047), preoperative coxa valga (OR= 4.54, P=0.005), and coxa vara (OR=2.85, P=0.03).

The incidence of periprosthetic femoral fractures is low using a triple tapered, collared cementless femoral stem with automated impaction through the DAA. Our findings agree with previous reports that have demonstrated women and preoperative valgus neck angle are risk factors for PFF.