Assessing the Impact of Femur Morphological Variations on Pediatric Hip Joint Biomechanics Using Statistical Shape Modeling

This dissertation aimed to (1) quantify morphological variations in the pediatric hip joint and (2) evaluate the sensitivity of an infant musculoskeletal model (MSM) to these variations, considering hip joint center estimation errors. A shape statistical model (SSM) of decedent infant femurs from the Ortolani collection was created using ShapeWorks, capturing key morphological features, such as variations in the femoral neck-shaft and anteversion angles. Seven synthetic femurs were generated from the SSM to create SSM-informed MSMs, which were systematically evaluated through kinematics and kinetics analyses in OpenSim. Incorporating the SSM led to slight changes in the pediatric MSMs’ kinematics but had negligible effects on kinetics. Nonetheless, the hip flexion angles from the model were consistent with literature on spontaneous kicking, demonstrating the model’s potential for modeling infant biomechanics. The dissertation introduces a novel framework for developing and assessing the robustness of integrating SSMs to create personalized MSM for infants.