Gait variability and biomechanical distinctions in individuals with functional ankle instability: a case-control...

Area of Science:

• Biomechanics
• Sports Medicine
• Orthopedics

Background:

• Ankle sprains are the most common sports injury, frequently leading to functional ankle instability (FAI).
• FAI is characterized by recurrent instability and neuromuscular deficits, impacting daily activities and athletic performance.
• Objective markers are needed to guide effective rehabilitation for FAI.

Purpose of the Study:

• To quantify lower limb biomechanical alterations during gait in individuals with FAI using 3D gait analysis.
• To identify objective kinematic markers associated with FAI for targeted rehabilitation.
• To compare gait parameters between FAI subjects and healthy controls.

Main Methods:

• A case-control study involving 31 matched pairs of FAI subjects and healthy controls.
• Propensity score matching was used to ensure subject comparability.
• 3D gait analysis with an infrared motion capture system (BTS SMART-D 400) was employed to collect kinematic data.
• Functional assessments included the Cumberland Ankle Instability Tool (CAIT), AOFAS scale, and VAS for pain.

Main Results:

• FAI subjects exhibited significantly altered gait, including changes in pelvic tilt, hip ad-abduction, and hip sagittal plane flexion.
• A notable decrease in maximum ankle dorsiflexion was observed in FAI individuals.
• Deviations in forefoot and hindfoot dorsiflexion angles were also significant in the FAI group.

Conclusions:

• Post-traumatic sensorimotor deficits following ankle injury lead to central nervous system-mediated motor control reorganization.
• Altered movement strategies in FAI manifest as modified kinematic coordination patterns across the hip, knee, and ankle.
• These findings underscore the complex biomechanical adaptations in FAI and inform the development of personalized rehabilitation programs.