Biomechanical comparison of the non-locking bone plate, locking bone plate, and double-rod clamp internal fixation in a canine femoral model.

Abstract

<h4>Background and aim</h4>Canine femoral fractures are prevalent in veterinary medicine, necessitating effective fixation methods to ensure stability and promote healing. Conventional bone plate fixation methods, including non-locking and locking plates, have inherent limitations, such as periosteal damage and mechanical failure. This study aims to evaluate the biomechanical performance of three fixation methods - non-locking bone plates, locking bone plates, and a novel double-rod clamp internal fixation system - using finite element analysis (FEA).<h4>Materials and methods</h4>A computed tomography-based canine femur model was created to simulate a midshaft commin-uted fracture with a 20 mm gap. Three fixation configurations were modeled: A non-locking bone plate, a locking bone plate, and a double-rod clamp system. FEA was performed to assess implant stress and proximal fragment displacement under physiological axial loading. Mesh refinement and multiple loading conditions were incorporated to enhance computational accuracy.<h4>Results</h4>The non-locking bone plate exhibited the highest implant stress (1160.22 MPa), surpassing the material yield strength and indicating a risk of mechanical failure. The double-rod clamp system demonstrated lower stress (628.34 MPa), whereas the locking bone plate had the lowest stress (446.63 MPa). Proximal fragment displacement was highest in the non-locking bone plate (2.37 mm), followed by the double-rod clamp system (0.99 mm), with the locking bone plate exhibiting the least displacement (0.34 mm), suggesting superior stability.<h4>Conclusion</h4>The double-rod clamp system emerged as a promising alternative, offering a balance between stability and stress distribution while minimizing periosteal damage. While the locking bone plate provided the greatest stability, the double-rod clamp fixation demonstrated favorable mechanical properties and could serve as a cost-effective and minimally invasive alternative in veterinary orthopedics.