Lead Leg Corrective Responses to Varying Slip Severity

Slips and falls account for large rates of injury and mortality in multiple populations. While previous research has examined the corrective responses elicited, it is still unclear which responses may break down during more severe slips. PURPOSE: To examine lead leg slip recovery corrective responses across slip severity following an induced slip. METHODS: One hundred participants were recruited for this study. Participant’s lower extremity gait kinematics and kinetics were collected during normal gait and an unexpected slip. The variables of interest were mean sagittal moments about the ankle, knee, and hip, during stance phase. Peak moments, and time to peak moments. The slip was classified based on slip severity, using heel slip distance, and velocity. Once classified, corrective responses were examined between groups using independent t-tests. Additionally, prediction equations for slip severity were created using a binary logistic regression model. RESULTS: After exclusions, the final sample included 64 participants for analyses, consisting of 37 non-hazardous slips, and 27 hazardous slips. The results from the logistic regression model suggest that as the average ankle moment increases in the slip period, the odds of experiencing a hazardous slip decrease (OR = 0.01, CI: 0.01-0.03). Further, as the time to peak hip extension (OR = 1.007, CI: 1.000-1.013) and knee extension moments (OR = 1.001, CI: 0.997-1.004) increase, the odds of experiencing a hazardous slip increase. CONCLUSIONS: Rapid lower extremity corrective responses appear critical in arresting the slip. While there are various strategies for slip recovery, our findings suggest that the primary recovery mechanism at the slipping hip may play a vital role in preventing the severe slip.