Prophylactic wiring vs. non-wiring in hip arthroplasty: finite element and cadaveric analysis of proximal femur biomechanics.

Abstract

Background: Intraoperative periprosthetic femur fracture is a serious complication in hip arthroplasty, affecting patient outcomes. This study explored the biomechanical properties of the proximal femur, specifically comparing prophylactic cerclage wiring to non-wiring techniques using finite element analysis (FEA) and cadaveric biomechanical testing.

Method: A finite element model of the proximal femur was constructed using Ansys software, allowing systematic assessment of both wiring area and technique to identify biomechanically optimal locations and configurations for cerclage placement. Twenty fresh cadaveric femurs were prepared according to standard protocols; the left femurs received cerclage wiring, while the right served as controls. Each femur was fitted with a femoral stem and tested under axial loading until catastrophic failure. Outcomes measured included ultimate load, seating load, subsidence distance, and energy absorption. Statistical analysis included the Shapiro-Wilk test for normality and independent t-tests for group comparisons.

Results: The wiring group demonstrated comparable biomechanical performance to the non-wiring group across all measured parameters. Energy absorption was similar between groups (41.9 ± 18.1 Nm vs. 41.0 ± 19.1 Nm, P = 0.918). No significant differences were observed in ultimate load (7.6 ± 2.1 kN vs. 7.7 ± 2.0 kN, P = 0.901) or seating load (3.1 ± 0.7 kN vs. 3.4 ± 1.4 kN, P = 0.589). Similarly, subsidence distance showed no intergroup difference (7.7 ± 2.6 mm vs. 7.7 ± 3.8 mm, P = 0.978).

Conclusion: Cerclage femoral wiring for prophylactic purposes during hip arthroplasty does not confer a significant biomechanical advantage over non-wiring techniques.