Extending Musculoskeletal Modelling Validation Beyond Gait: Knee Loading and Kinematics During Daily Activities

Predicted knee contact force magnitudes from personalized MSK models match instrumented implant measurements across five CAMS-Knee ADLs, with RMSE 0.46 BW and R2 = 0.81.

• Why it matters: Validation is needed to translate MSK modelling into clinical use, but prior checks were limited to single activities like gait or bending, masking activity-specific errors.
• What they did: Using motion-capture data from 184 activity cycles in six subjects performing five ADLs, personalized models incorporated anthropometric, radiographic, and implantation data plus a 6-DOF elastic-foundation contact model and surgically balanced ligament model.
• The result: Level walking showed the highest accuracy, while stair descent had the largest discrepancies; implant kinematics matched fluoroscopic trends and EMG timing was broadly consistent, though gastrocnemius activation was poorly estimated during stair descent and downhill walking.