Knee osteoarthritis treatment may advance with 3D printed soles that passively modify gait biomechanics and reduce medial knee loading.
A prototype 3D printed shoe sole replicates key biomechanical effects of toe out gait retraining, offering a low-effort intervention for knee osteoarthritis, particularly when sustained retraining is challenging.
Knee osteoarthritis severity is influenced by mechanical loading across the joint. This study examined knee adduction moments, a surrogate for medial knee loading. The team developed rotational and variable stiffness (RVS) soles to encourage a toe out gait pattern without real-time feedback.
21 healthy adults participated in trials comparing control shoes and RVS shoes, analyzing motion capture data. After toe out retraining, the second peak knee adduction moment decreased significantly. RVS shoes reduced this moment by 16.3%, indicating passive effects comparable to moderate retraining conditions. Additionally, the shoes decreased knee adduction angular impulse by 8.6%, an improvement not seen with retraining alone.
These results suggest that shoe design can effectively alter loading during walking, minimizing reliance on patient compliance. However, further research is essential to assess comfort, adherence, and long-term effectiveness in knee osteoarthritis patients.