Altering Shank-Rear-Foot Joint Coupling During Gait With Ankle Taping in Patients With Chronic Ankle Instability and Healthy Controls.

Context: Lateral ankle sprain (LAS) is one of the most common injuries in active individuals. Chronic ankle instability (CAI) is a condition that commonly occurs after LAS and is associated with long-term disability and a high risk of multiple ankle sprains. Ankle taping is a commonly used intervention for the prevention of ankle sprains.

Objective: To analyze the ankle-joint coupling using vector coding during walking and jogging gait with the application of ankle tape and without ankle tape in young adults with and without CAI.

Design: Observational laboratory study design. Patients walked and jogged on an instrumented treadmill while taped and not taped. Fifteen strides for each subject were collected and analyzed using a vector-coding technique to compare magnitude coupled motion, ratio of coupled motion, and the variability (VCV) within groups. Within-group means and 90% confidence intervals (CI) were compared between the taped and nontaped condition, and where the CIs did not overlap was considered significant.

Setting: A 12-camera 3D motion-capture system with instrumented treadmill.

Patients: 12 patients with CAI and 11 healthy controls.

Main Outcome Measures: Magnitude to coupled motion, ratio of coupled motion, and the VCV of shank-rear-foot joint coupling.

Results: Magnitude of coupled motion and VCV were significantly lower in the taped condition than in the nontaped condition in both groups. Magnitude differences were identified near initial contact during walking and during swing phase of jogging. VCV differences were identified throughout the gait cycle at both walking and jogging. No differences were identified in theta between tape and nontaped conditions.

Conclusions: A decrease in the magnitude of coupled motion and VCV may represent a protective mechanism of ankle taping in CAI and healthy patients during gait.