Evaluation of anatomical consistency of three subject-specific ankle joint modelling approaches

In this study, three ankle joint models with increasing level of personalisation are compared within a standard musculoskeletal model (MSKM) of the lower limb, integrated with individual ligaments and articular surfaces from magnetic resonance images (MRI) to assess their anatomical consistency. Kinematics variations between the models were significant, in two cases leading to unphysiological ligament elongation and cartilage co-penetration, but did not impact on the kinetic output of the MSKM. The standard MSKM indeed implicitly assumes the contribution of ligament and contact deformation to the joint equilibrium as negligible. This assumption was however verified only for the most personalized ankle joint model. Anatomical consistency of joint models should be verified to guarantee the reliability of MSKMs’ outputs, particularly when joint reaction analysis is performed.