🔍 Key Findings
- Simulated quadriceps and gastrocnemius forces increased proportionally with axial load in all three femoral fixation models.
- Model 2 (rigid fixation) resulted in subphysiologic quadriceps forces and abnormally high gastrocnemius forces, reducing model fidelity.
- Models 1 and 3 (with hip mobility) produced more physiologic quadriceps and force ratios, especially under 30–40% bodyweight loads.
- Force ratios were significantly lower in rigid fixation (Model 2) compared to hip-mobile models (p = .007), suggesting model design affects simulated muscle coordination.
- Joint angles (stifle and hock) remained within acceptable limits, though slight flexion occurred with increasing load.
- Relative foot position differed by ~3.9 mm between models 2 and 3, with model 2 showing a more caudal position.
- Model 3 preserved benefits of hip mobility while allowing radiographic documentation, making it a preferred setup for future studies.
- The study suggests that models used in feline stifle stabilization research may underestimate physiologic forces, especially with rigid fixation designs.