Chronic Ankle Instability-Related Outcomes Associate With Ankle-Joint Loading During Walking.

CONTEXT

Recurrent trauma and altered biomechanics in those with chronic ankle instability (CAI) have been linked to altered joint loading. Previous studies revealed that patients with CAI exhibit altered joint contact force (JCF) profiles relative to uninjured individuals during walking and landing. Identifying more easily obtainable outcomes that are associated with ankle JCF in those with CAI would reduce the knowledge gap between loading profiles at the ankle joint and outcomes related to CAI.

OBJECTIVE

To quantify how ankle JCF, structural measures, postural control, and walking biomechanics interrelate in patients with CAI and how CAI variables predict ankle JCF.

DESIGN

Cross-sectional study.

SETTING

Research laboratory.

PATIENTS OR OTHER PARTICIPANTS

A total of 21 patients with CAI (7 men, 15 women; age = 23 ± 4 years, height = 171.6 ± 8.3 cm, mass = 71.7 ± 12.1 kg).

MAIN OUTCOME MEASURES

Triaxial peaks, impulses, and loading rates of ankle JCF were captured. Rearfoot alignment, Star Excursion Balance Test reach distances, weight-bearing lunge test score, and peak ankle angles and moments during the stance phase of walking were also recorded. Partial Pearson correlations and forward stepwise regressions were used to examine the relationships among the ankle JCF variables and traditional CAI-related impairments.

RESULTS

Less compressive JCF variables were associated with more rearfoot varus alignment ( = -0.53, = .02) and greater peak inversion moment while walking ( = -0.46, = .041). Greater posterior JCF was associated with greater peak eversion ( = 0.55, = .01) and dorsiflexion moments while walking ( = -0.48, = .03) as well as less rearfoot varus alignment ( = 0.51, = .02). Similarly, greater lateral JCF variables were associated with greater dorsiflexion moment while walking ( = 0.49, = .03) as well as less rearfoot varus alignment ( = -0.52, = .02). Multivariate regression models partially explained ankle JCF while walking in those with CAI.

CONCLUSIONS

Although our results suggest potential associations between gait biomechanics, structural measures, and postural control with ankle JCF, further research is needed to determine if targeting these factors during therapeutic interventions would modify mechanical loading at the ankle joint during walking.