Biomechanical Evaluation of a Hybrid Fixation Strategy: Enhancing Intramedullary Nail Stability With a Trochanteric Stabilization Plate in Unstable Intertrochanteric Fractures With Lateral Wall Collapse.

Introduction Unstable reverse oblique intertrochanteric fractures with lateral wall collapse present a unique fixation challenge due to the absence of a lateral buttress. When treated with standard implants, this structural deficit frequently leads to construct failure through varus malunion and medialization of the femoral shaft. A device developed to provide rigidity for the maintenance of fracture reduction would bridge this gap. This study evaluates the biomechanical performance of a hybrid fixation strategy utilizing a Trochanteric Stabilization Plate for Nails (TSPN) in combination with an intramedullary nail (IMN) for such fractures using finite element analysis (FEA) and mechanical testing. Methods The study compared standard IMN fixation to a hybrid IMN-TSPN construct by simulating fracture scenarios in a validated femur model and performing mechanical tests on composite bone specimens (total n = 10; n = 5 per group). Finite element analysis quantified computational deformation, stress distribution, and elastic strain, while experimental physical tests measured construct stiffness and failure load under static axial compression. Statistical significance for experimental outcomes was evaluated using the non-parametric Mann-Whitney U test with a Bonferroni correction. Results The IMN-TSPN hybrid construct demonstrated a significant 1.85-fold increase in experimental structural rigidity (p = 0.008) and higher physical failure thresholds compared to IMN alone. Computationally, TSPN augmentation substantially reduced maximum fracture-gap displacement, peak elastic strain, and peak von Mises stress. The TSPN effectively redistributed loading and minimized total construct deformation. Conclusion In a composite bone model under static axial loading, augmenting an IMN with a TSPN significantly increased construct stiffness and reduced deformation compared to IMN alone. These findings suggest a biomechanical advantage that warrants further testing in clinically representative, dynamic models.