EFFECTS OF EXTERNAL BIOFEEDBACK ON BIOMECHANICS AND ANKLE JOINT HEALTH IN INDIVIDUALS WITH CHRONIC ANKLE INSTABILITY

Individuals with chronic ankle instability (CAI) often demonstrate abnormal biomechanical patterns which may be associated with the onset of posttraumatic osteoarthritis (PTOA). There is a lack of interventions capable of changing gait impairments and targeting the sensorimotor dysfunction in this population. The use of external focus of attention biofeedback during walking has shown to be capable of improving biomechanics in real-time, however, the retention of these changes needs to be further explored prior to implementing into clinical practice. Further, technological advancements have shown ultrasonography of the talar articular cartilage is a plausible mechanism to monitor joint health, yet the associations of ultrasound-based images and biomechanical patterns in patients with CAI remains unknown. This dissertation focused on three main research questions: 1) Does incorporating an auditory biofeedback device during common rehabilitation exercises improve biomechanics during a single session, 2) Is there a relationship between abnormal walking biomechanics in patients with CAI and ultrasound-based measures of talar articular cartilage health, 3) Does incorporating an auditory biofeedback device into a 2-week gait training program improve biomechanics and ankle joint health in patients with CAI compared to a control condition. First, we identified auditory biofeedback is effective at improving biomechanics during functional exercises in addition to its improvements in gait. Next, we found significant correlations between abnormal walking biomechanics, talar cartilage thickness, and echo intensity. Finally, our 2-week gait training intervention has shown to be effective in improving walking gait in patients with CAI immediately and up to 1 week following the intervention. The findings of this dissertation have found the relationship between biomechanical gait patterns and ankle joint health which will guide clinical practice in identifying modifiable factors to potentially mitigate the onset of PTOA after an ankle injury. This dissertation has also identified a clinically applicable mechanism to improve the abnormal biomechanics that are related to cartilage joint health.