The Relationship Between the Kinetic Parameters, Electromyography Activity, and Kinesiophobia Among Copers, Chronic Ankle Instability, and Healthy Subjects During Gait Initiation: A Cross-Sectional Study.

Context: Following a lateral ankle sprain, chronic ankle instability (CAI) subjects show recurrent episodes of giving way, while copers do not exhibit giving way and overcome the challenging condition of postural control. During gait initiation (GI), individuals with CAI reveal shorter center of pressure (COP) displacement and earlier muscle activity compared with healthy controls. Copers have not been previously compared with healthy controls and individuals with CAI during GI.

Design: The study design was cross-sectional.

Method: Sixty participants (20 CAI, 20 copers, and 20 healthy controls) with a right (dominant) limb injury participated in the study based on inclusion and exclusion criteria. The short form of the Tampa Scale of Kinesiophobia was filled out. Participants performed GI with the nonaffected leg on the force plate that was synchronized with Electromyography Megawin for 2 strides. GI was divided into 3 phases based on COP excursion (S1, S2, and S3). Onset time and electromyography activity of both soleus and tibialis anterior muscles were analyzed along with maximum and mean excursion and velocity of COP excursion in the anterior-posterior and medial-lateral directions and the total phases of GI.

Results: The results indicated that the copers had a significantly higher peak of COP excursion in the medial-lateral direction during S2 (P = .029), S3 (P = .018), and total phases (P = .018) of GI compared with the individuals with CAI. Additionally, individuals with CAI showed earlier activation of the right soleus compared with healthy controls (P = .022). There was a significant difference in short form of the Tampa Scale of Kinesiophobia scores between individuals with CAI and other groups (P < .001).

Conclusion: The findings demonstrated that individuals with CAI had earlier soleus activation and supraspinal alteration compared with controls. Copers who had lower Tampa Scale of Kinesiophobia scores exhibited an increased peak of COP excursion in the medial-lateral direction during GI compared with individuals with CAI.