PhD defense by Christine Mary Dzialo
Personalized musculoskeletal modeling: Bone morphing, knee joint modeling and applications
14.03.2019 kl. 10.00 - 15.00
Personalized Musculoskeletal Modeling:
Bone Morphing, Knee Joint Modeling and Applications
Knee osteoarthritis (KOA) is a slow degenerative disease of the knee joint that has been recognized as one of the leading causes of global disabilities due to the irreversible deterioration. Spite the significant burden of KOA, there seems a lack in effective treatment methods at early stages of the disease.
The importance of personalized computational modeling has been highlighted as of late; however, there is a knowledge gap when applying these models to early stage KOA patients (pre-surgical interventions). It is known that patients with KOA have altered biomechanics for a variety of reasons which may or may not be linked to each other: increased pain, stiffening of the joint, malalignment, previous injuries, instability, etc., further emphasizing the need for individualization.
This dissertation focused on personalized musculoskeletal modeling pertaining to three main areas: First, computationally efficient novel moving-axis joint models utilizing subject-specific bone geometries were developed, applied to two joints (tibiofemoral and patellofemoral), and evaluated against experimental kinematic data resulting in more realistic secondary joint kinematics than commonly used hinge joints. Second, a subject-specific multi-scale model was established, which allows for investigation of how varying biomechanics and orthoses interventions can affect the internal loads of the body and influence the stresses/strains of anatomical features.
The process of developing and combining musculoskeletal modeling and finite analysis was presented as a workflow that provides a methodological groundwork for future clinical applications. Thirdly, the success of non-invasive interventions aimed at treating early-stage medial KOA such as lateral wedge insoles (LWI) and gait modifications (toe-in, toe-out, and wide stance walking) has not always been exclusive.
The last part of this dissertation explores what might contribute to these inconsistencies in patient responses by examining generic vs patient-specific musculoskeletal modeling techniques, and analyzing treatment outcomes based on the patients as individuals vs a group.
Although limited by a small sample size, we found that a ‘one-size-fits all’ gait alteration aimed at minimizing medial contact loading did not exist, suggesting the importance of individually assigned interventions. Moreover, the different musculoskeletal modeling techniques lead to differences in medial contact forces. Highlighting the importance of further investigation of scaling approaches prior to being able to use such models in the clinical setting to assist in prescribing patient optimized gait alterations.
The research conducted during this PhD is merely a starting point in hopes of future researchers better validating personalized knee joint models and progressing personalized musculoskeletal modeling into to the clinical setting.
Department of Materials and Production
Fibigerstræde 16,room 1.201, 9220 Aalborg Ø