Electromyographic Validation of the DMA Clinical Pilates Method for Classifying Muscle Impairments in Chronic Ankle Instability

Background/Objectives: Chronic ankle instability is a common issue after lateral ankle sprain. The DMA Clinical Pilates method hypothesizes impairments in tibialis anterior and fibularis longus muscles. Methods: A total of 14 adults with chronic ankle instability, and 15 recovered and 16 healthy individuals were prospectively recruited and assessed for lower back, hip, knee, and ankle muscle activities during dominant and non-dominant sides single-leg stand on stable and unstable surfaces using wireless surface electromyography. Results: The study found consistent dysfunction in tibialis anterior muscle activity in adults with chronic ankle instability when compared with healthy adults during single-leg stand on stable and unstable surfaces, and against recovered individuals on unstable surface. As compared to healthy controls, chronic ankle instability group showed higher vastus lateralis activation during dominant side single-leg stand across surface conditions and during dominant side single-leg stand, while the higher dominant side longissimus dorsi activity on stable surface changed to higher dominant side medial gastrocnemius activity on unstable surface. As compared to recovered controls, chronic ankle instability group also showed higher gluteus medius and fibularis longus muscle activities on unstable surface. Conclusions: Tibialis anterior muscle is the main dysfunction among individuals with chronic ankle instability side.