Author ORCID Identifier

Date Available


Year of Publication


Degree Name

Doctor of Philosophy (PhD)

Document Type

Doctoral Dissertation




Biomedical Engineering

First Advisor

Dr. Babak Bazrgari

Second Advisor

Dr. Michael A. Samaan


Marfan syndrome (MFS) is a genetic condition that is associated with altered muscle composition, which leads to muscle dysfunction. People with MFS exhibit high instances of lower extremity (LE) joint pain that inhibits their ability to perform activities of daily living, such as walking. Despite these detrimental impacts of MFS, there have been no attempts to characterize the effects of MFS on LE joint loading and health during walking that are associated with LE pain and dysfunction. As people with MFS exhibit a high incidence rate of osteoarthritis (OA), the need to understand the potential alterations in LE extremity mechanics during gait that are associated with poor joint health in the MFS population is warranted. Therefore, the objective of this study was to investigate LE joint mechanics during walking in people with MFS.

We performed a cross-sectional assessment in people with MFS and healthy, asymptomatic controls, where sagittal plane LE joint mechanics were assessed during a fixed velocity gait task. Participants with MFS were required to have a confirmed case of MFS via genetic testing or qualification via the Ghent criterion and were cleared for exercise by our study physician. Following an extensive literature review, a sagittal plane traditional gait analysis and musculoskeletal (MSK) modeling were performed on people with MFS to assess lower extremity gait mechanics. For our traditional gait analysis, an assessment of peak lower extremity joint angles, peak joint moments, joint moment impulses, and joint moment durations was performed. In terms of MSK modeling, peak hip, knee and ankle muscle force production, muscle force impulse, joint contact force (JCF), JCF impulse, total LE joint loading (summation of the average LE JCF for each joint) and each joints contribution to total LE joint loading was assessed.

The results showed that people with MFS ambulated with more hip flexion, knee and ankle dorsiflexion, which places the LE in a more flexed position while walking. In turn, the more flexed LE places a larger demand on the hip and knee extensor and ankle plantarflexor musculature (i.e., higher joint moments) during the stance phase of gait in order to maintain LE stability and support. Participants with MFS also exhibited altered muscle force production and JCF loading patterns compared to healthy controls. Both traditional gait analysis and musculoskeletal modeling, demonstrate that people with MFS ambulate with altered LE kinematics and moments, muscle force production and JCF patterns. The gait mechanics, muscle force production, and joint contact loading patterns described in this dissertation provides clinicians with preliminary information that may be used to develop gait-related interventions to improve LE joint function and health in people with MFS.

In conclusion, people with MFS exhibit similar gait mechanics as other populations that are predisposed to OA. These findings may be responsible for the high instances of early onset OA seen in the MFS community but will need to be investigated further in order to better understand the association between gait mechanics and joint health in the MFS population.

Digital Object Identifier (DOI)

Funding Information

This study was supported by the following grants Marfan Foundation Grant (2021-2023) National Institutes of Health KL2-TR001996 (2021-2023) National Institutes of Health K01HL149984 (2021-2023) National Institutes of Health UL1TR001998 (2021-2023)

Available for download on Wednesday, May 15, 2024