Effects of Gait Retraining on Lower Extremity Biomechanics

The purpose of this proposed study is to investigate both the acute and chronic response of frontal plane knee moment after gait retraining and to assess the effects on the biomechanics of the contralateral side. Fifty-one patients diagnosed with tibiofemoral joint osteoarthritis (TFJ OA) will be recruited to participate in the proposed study. Participants will complete baseline trials to assess gait kinematic and kinetic parameters. Following baseline, each participant will perform six conditions of the foot progression gait or three conditions of the trunk lean gait modifications to determine which strategy is most effective in reducing frontal plane knee moment. Participants will then be randomized to either the control or experimental group based on their identified preferred strategy. Participants will complete eight gait retraining sessions using patient-specific gait modifications (tailored foot progression and tailored lateral trunk lean), or normal gait (control) during the training period. A fading feedback design will be implemented. Real-time haptic biofeedback will be provided on every step during the first two weeks and reduced by 25% every subsequent two weeks. No feedback will be provided during baseline and at testing sessions. Measures of pain and function will also be collected at all testing sessions. Variables of interest include ankle, knee, hip sagittal and frontal plane moments. In addition, sagittal and frontal plane impulse will also be assessed. Descriptive statistics will be calculated for foot progression angle, trunk lean angle, frontal and sagittal plane hip, knee, and ankle angles as well as moments. Descriptive statistics for frontal plane knee impulse will also be calculated. A multivariate analysis of variance (MANOVA) will be conducted to compare frontal plane knee moment, frontal plane knee impulse and the absolute sagittal plane moment will be compared across three groups at four different time points. Repeated measures analysis of variance (ANOVA) will be conducted to compare both sagittal and frontal plane joint biomechanics for the contralateral limb. The p-value will be set at .05.