Numerical Simulation of Nickel–Titanium Memory Alloy Patellar Converters in Transverse Patellar Fractures and Its Guidance for Rehabilitation Training

To further refine rehabilitation protocols for transverse patellar fractures, this study conducted numerical simulations in Abaqus to investigate the interaction between a nickel–titanium shape-memory-alloy patellar concentrator and fractured patellar bone under variations in patellar loading, quadriceps muscle tension, knee-flexion angle, and fracture-site width. Lower knee-flexion angles primarily generated bending moments in the patellar concentrator, whereas greater flexion angles primarily generated tensile forces. Across the simulated knee-flexion range of 0–150°, the predicted quadriceps muscle force ranged from 240 to 670 N. Based on the simulated mechanical response, under the prescribed modeling assumptions, the 60–90° knee-flexion range showed a comparatively favorable balance between predicted fracture closure and implant loading. Comparison with previously published computational studies showed that the loading and angular conditions examined in this study were within the ranges reported in the literature, while extending the analysis to less frequently studied flexion conditions. However, because direct experimental validation, mesh-convergence testing, and comprehensive sensitivity analysis were not included, these values should be interpreted as model-based estimates requiring further experimental and clinical validation.