Is suture-based cerclage biomechanically superior to traditional metallic cerclage for fixation of periprosthetic femoral fractures: A matched pair cadaveric study

Background

While traditional metallic cerclage remains the primary method in clinical application, non-metallic cerclage systems have recently gained popularity due to low risks of soft tissue irritation and bone intrusion. The objective of this study was to assess the performance of a novel non-metallic suture-based cerclage in comparison to traditional metallic cerclage cables for fixation of periprosthetic femoral fractures.

Methods

An extended trochanteric osteotomy was performed on eight pairs of cadaveric femora, followed by reduction using either metallic cerclages (Group I) or the suture-based cerclage (Group II). A modular tapered fluted stem was then implanted in each specimen. The fragment translation during canal preparation and stem implantation was quantified using laser-scanning. Subsequently, each specimen underwent 500 cycles of multiaxial loading, with fragment translation and stem subsidence measured using a motion capture system.

Findings

Following stem implantation, specimens in Group II exhibited a significantly greater lateral fragment translation (466 μm vs 754 μm, p = 0.017). However, there were no significant differences in anterior and distal translation between groups (p > 0.05). During multiaxial loading, the average stem subsidence in Group I was 0.36 mm (range, 0.04–1.42 mm), compared to 0.41 mm (range, 0.03–1.29) in Group II (p > 0.05). No significant difference was found in fragment translations between the two groups (p > 0.05).

Interpretation

The suture-based cerclage system exhibited comparable biomechanical performance in fixation stability to conventional metallic cerclage cables. Yet, it was associated with a larger residual lateral gap between the fragments following stem implantation. Ultimately, the choice of fixation method should account for multiple factors, including patient characteristics, surgeon preference, and bone quality.