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Updated: May 6, 2026
Evaluating Postural Control and Lower-extremity Muscle Activation in Individuals with Chronic Ankle Instability
Published on: September 18, 2020
Ankle kinematics and muscle activity in functional ankle instability
Bradley J Monteleone1, Janet L Ronsky, Willem H Meeuwisse
1*McCaig Center for Joint Injury and Arthritis Research, University of Calgary, Calgary, Alberta, Canada; †LifeMark Health Sport Medicine Centre, Kelowna, British Columbia, Canada; ‡Faculty of Medicine, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada; and §Departments of Orthopaedic Surgery and Biomedical Engineering and School of Kinesiology, University of Michigan, Ann Arbor, Michigan.
Patients with functional ankle instability (FAI) exhibit greater ankle dorsiflexion and tibialis anterior muscle activity during lateral hopping. These findings may indicate predispositions or adaptations to previous ankle injuries.
Area of Science:
- Biomechanics
- Sports Medicine
- Orthopedics
Background:
- Functional ankle instability (FAI) is common after ankle injuries, increasing reinjury risk.
- Understanding FAI's impact on movement is crucial for prevention and rehabilitation.
Purpose of the Study:
- To investigate the effects of FAI on ankle kinematics and muscle activity during a lateral hop.
- To compare movement patterns between individuals with and without FAI.
Main Methods:
- A cross-sectional study comparing a control group (n=12) with an FAI group (n=12).
- Subjects performed lateral hops over an obstacle onto force platforms.
- Ankle kinematics and tibialis anterior muscle activity were measured.
Main Results:
- The FAI group showed significantly greater ankle dorsiflexion at ground contact (82.4° vs. 75.2°).
- Tibialis anterior normalized muscle activity was higher in the FAI group at ground contact (0.27 vs. 0.16).
Conclusions:
- FAI is associated with increased dorsiflexion and tibialis anterior activity during lateral hopping.
- These biomechanical differences may stem from injury predisposition, pre-existing factors, or adaptations to prior injuries.
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