Effect of ankle range of motion on high knee flexion posture kinematics

Ankle range of motion (RoM) may impact knee and hip range of motion in high knee flexion postures (>120°). The purpose of this study was to quantify how differences in ankle sagittal plane RoM affects knee and hip flexion and abduction kinematics. Twenty-eight low and twenty-six high ankle RoM participants completed dorsiflexed and plantarflexed kneels from which the kinematics during the static phase were compared. Significant interactions indicated that high RoM participants exhibit 9.1° more hip flexion during the dorsiflexed kneel, and high RoM females exhibit 6.1° more knee flexion than low RoM females. High RoM participants also exhibit an average 4.2° more knee flexion. These findings suggest that changes in ankle mobility, which may come about from factors such as age, injury, footwear, or environmental terrain, may alter an individual’s movement patterns during high knee flexion postures, thereby alternatively loading structures of the knee joint.