A Footwear-Foot-Knee Computational Platform for Exploring Footwear Effects on Knee Joint Biomechanics

The purpose of this study was to investigate comprehensive knee joint responses to wedged footwear intervention with lateral inclination angles of 0A degrees, 5A degrees, and 10A degrees at three stance instants in a gait cycle. A footwear-foot-knee finite element model reconstructed from magnetic resonance images of a healthy male subject was validated through a cadaveric experiment and used to predict knee joint loading. The model was driven by the ground reaction force and subject-specific muscle forces to simulate three stance instants, namely the first peak, valley, and second peak of the ground reaction force. Based on the gait analysis data for the same subject, muscle forces were calculated using a musculoskeletal model. The finite element predictions indicated that the medial compartment of the knee joint showed higher loading than that of the lateral one and that the wedged footwear diminished stress, strain, and contact pressure in the medial compartment at all three stance instants. A 10A degrees wedge angle yielded a stronger effect than that obtained with a 5A degrees angle at the three stance instants. Increased gastrocnemius lateralis activity and decreased gastrocnemius medialis activity were found with laterally wedged footwear intervention. The footwear-foot-knee computational platform is promising for exploring footwear effects on knee joint biomechanics.