Bone morphology influences asymptomatic knee kinematics across the flexion range: a dynamic CT study

Considerable inter-individual variability in knee kinematics exists even within asymptomatic populations, yet the extent to which this variability relates to underlying morphology remains poorly understood. This study aimed to identify morphological features associated with asymptomatic knee kinematics across the full knee flexion range. Dynamic CT data from 100 asymptomatic participants performing a knee flexion-extension movement were analysed, of which 73 knees met the inclusion criteria. Tibiofemoral and patellofemoral kinematics were extracted from the dynamic scans, while morphological features of the femur, tibia and patella were automatically quantified from the static CT scan. Associations between morphology and dynamic knee kinematics were assessed using mixed-effects models across the full knee flexion range. Tibial plateau morphology and the lateral femoral condyle radius were significantly associated with tibiofemoral internal-external rotation and anterior-posterior translation. Regarding patellofemoral kinematics, Wiberg angle was associated with patellar flexion, whereas Wiberg index, patellar width, and medial and lateral trochlear inclination were associated with patellar tilt and mediolateral translation. Several of these associations varied with knee flexion angle, indicating that morphology-kinematics relationships are dynamic. Improved understanding of these relationships provides a foundation for future morphology-based prediction models that may contribute to personalized treatment strategies.