Search Results

You are looking at 1 - 2 of 2 items for

  • Author: Lisa Chinn x
Clear All Modify Search
Restricted access

C. Collin Herb, Lisa Chinn and Jay Hertel

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.

Restricted access

C. Collin Herb, Lisa Chinn, Jay Dicharry, Patrick O. McKeon, Joseph M. Hart and Jay Hertel

Chronic ankle instability (CAI) results in longstanding symptoms and subjective feelings of “giving way” following initial ankle sprain. Our purpose was to identify differences in joint coupling and variability between shank internal/external rotation and rearfoot inversion/eversion throughout the gait cycle of CAI subjects and healthy controls. Twenty-eight young adults participated (CAI, n = 15, control, n = 13). Kinematics were collected while walking and jogging on a treadmill. A vector coding method in which direction (θ) and magnitude of the angle-angle relationship and stride-to-stride variability (VCV) in shank-rearfoot coupling were calculated. In walking, the CAI group demonstrated lower θ, indicating a greater proportion of rearfoot-to-shank motion, compared with the control group in early and late swing. The CAI group had higher magnitude, indicating greater combined motion between the two segments, in early swing, but lower magnitude, indicating less combined motion, during late swing. The CAI group also had lower VCV measures, indicating less stride-to-stride variability during stance. In jogging, the CAI group had lower θ measures than the control group during stance and swing. Differences in shank-rearfoot coupling of the CAI group may be related to changes in sensorimotor control and lead to further instances of instability.