Chronic ankle instability patients exhibit higher variability in lower extremity joint-coupling variability during...

Area of Science:

• Biomechanics
• Motor Control
• Sports Medicine

Background:

• Chronic ankle instability (CAI) is linked to biomechanical changes during landing.
• Previous research on CAI has focused on gait, with limited data on jumping tasks.
• Joint coupling variability may indicate sensorimotor deficits in CAI populations.

Purpose of the Study:

• To compare lower extremity joint coupling variability during a drop-vertical jump (DVJ) between individuals with CAI and healthy controls.
• To investigate the role of joint coupling variability as a potential biomarker for sensorimotor control in CAI.

Main Methods:

• Twenty-eight young, active participants (14 CAI, 14 controls) were recruited.
• A 3D motion capture system recorded kinematics during 15 DVJ trials per participant.
• Vector coding analysis quantified joint coupling variability in sagittal and frontal planes for hip, knee, and ankle joints.

Main Results:

• The CAI group demonstrated significantly higher joint coupling variability in the hip frontal-ankle sagittal, knee sagittal-ankle frontal, and knee sagittal-ankle sagittal planes.
• These differences were observed both before and after ground contact during the DVJ.
• Increased variability may reflect adaptive strategies or impaired sensorimotor control in individuals with CAI.

Conclusions:

• Individuals with CAI exhibit altered lower extremity joint coupling variability during DVJ compared to controls.
• These findings suggest potential sensorimotor adaptations or deficits in response to CAI and the DVJ task.
• Clinicians should acknowledge the unique task constraints of DVJ in CAI rehabilitation programs.