Periprosthetic femoral fracture following hip arthroplasty : which component design and fixation method has the lowest risk of reoperation?

Aims: Periprosthetic femoral fracture (PPFF) is a major complication following hip arthroplasty. This study examined the influence of femoral component design and fixation method on the risk of reoperation for PPFF.

Methods: We analyzed data on femoral component type use for primary hip arthroplasty stems reported to the Norwegian Arthroplasty Register and the Norwegian Hip Fracture Register from 1 January 2005 to 31 December 2023. The study included 187,576 well-documented femoral components used in hemi- and total hip arthroplasties which were assessed by Cox regression. The femoral components were categorized into five groups: 1) cemented composite beam (n = 30,415), and two types of cemented polished taper-slip components; 2) double-tapered (n = 52,255); 3) triple-tapered (n = 13,894), and two types of uncemented femoral components; 4) wedged collarless (n = 38,389); and 5) wedged collared (n = 40,853). Endpoint was reoperation for PPFF (revisions and osteosyntheses).

Results: A total of 1,398 femoral components (0.7%) were reported with a reoperation due to PPFF. The risk of reoperation was significantly higher for cemented double-tapered (adjusted hazard rate ratio (aHRR) 4.0 (95% CI 3.1 to 5.2), cemented triple-tapered (aHRR 4.0 (95% CI 2.9 to 5.6)), uncemented wedged collarless (aHRR 7.3 (95% CI 5.6 to 9.5)), and uncemented wedged collared (aHRR 3.5 (95% CI 2.6 to 4.6)) components compared to cemented composite beam components. Cemented triple-tapered prostheses exhibited a similar risk of reoperation (aHRR 1.0 (95% CI 0.8 to 1.3)) to cemented double-tapered components. Uncemented wedged collarless prostheses were associated with a higher risk of PPFF (aHRR 2.1 (95% CI 1.8 to 2.5)) compared to uncemented wedged collared designs.

Conclusion: To minimize the risk of PPFF, cemented composite-beam femoral components should be the surgeon's preferred choice. If cementing is not an option, uncemented wedged collared components are the best alternative. Opting for a cemented triple-tapered design does not improve outcomes compared to double-tapered component.