Static Balance Of Knee Crutch Users Before And After The Addition Of A Shoe

The knee crutch device is an assistive mobility device used by individuals with ankle and/or foot injuries who are unable to bear weight on one of their legs. This device provides hands-free mobility compared to traditional crutch devices though has been shown to have a large impact on standing balance of the wearer. One reason for this could be the current knee crutch design, whereby the distal end does not resemble the size nor shape of an anatomical foot. Attaching an adjustable shoe component will increase the base of support of the device, potentially aiding balance. PURPOSE: To determine the effects on static balance after adding a novel shoe component to the knee crutch device. METHODS: Nine healthy young adults (4 female, 5 male, age 20 ± 2 years) stood on a force plate under three conditions: normal, wearing the original knee crutch, and wearing the modified knee crutch with shoe. Three trials were performed with eyes closed and hands-on-hips for 20-seconds. The shoe attachment was adjusted to match participant shoe size. Path length of postural sway (measured in cm) was averaged across the trials of each condition, and then tested for differences using repeated measures ANOVA with follow-up paired t-tests. RESULTS: Repeated measures ANOVA revealed significant differences between conditions (F = 30.4, p < 0.001). Follow up t-tests indicated differences between baseline and crutch (baseline = 25.9 ± 4.3 cm, crutch = 63 ± 18.4 cm, p < 0.001), crutch and shoe (shoe = 29.6 ± 11.5 cm, p < 0.01), but not baseline and shoe. CONCLUSION: Adding an adjustable foot to the knee crutch device mitigated static balance deficits associated with the limited base of support of the standard knee crutch.