People With Marfan Syndrome Utilize an Ankle Dominant Strategy to Perform the Sit-to-Stand Task

Area of Science:

• Biomechanics
• Connective Tissue Disorders
• Human Movement Science

Background:

• Marfan syndrome (MFS) is a genetic connective tissue disorder affecting fibrillin-1.
• MFS is linked to muscle weakness and joint pain, particularly in the lower extremities (LE).
• Limited understanding exists regarding LE joint mechanics in individuals with MFS during functional tasks.

Purpose of the Study:

• To investigate and compare LE joint mechanics during the sit-to-stand (STS) task between individuals with MFS and healthy controls.
• To identify specific kinematic and kinetic differences during STS in MFS.

Main Methods:

• A cohort of 16 individuals with MFS and 16 matched controls performed the STS task at a self-selected pace.
• Evaluated parameters included peak extensor moments, moment impulses, moment durations, task completion time, and total support moment (TSM) contributions from each LE joint.

Main Results:

• Individuals with MFS demonstrated longer STS task completion times compared to controls.
• MFS group showed lower peak knee extensor moments but higher peak ankle plantar flexor moments.
• Higher LE joint extensor moment impulses and durations were observed in the MFS group.
• The MFS group utilized a higher TSM, with a greater contribution from the ankle joint.

Conclusions:

• Individuals with Marfan syndrome exhibit significantly altered LE joint mechanics during the STS task.
• MFS patients adopt a more ankle-dominant strategy for STS, potentially influencing joint pain and function.
• These findings highlight the need for targeted interventions addressing LE biomechanics in MFS management.