TREADMILL PERTURBATION REACTIVE BALANCE RATING; A NEW INDICATOR OF FALL RISK IN OLDER ADULTS

Abstract

Background: Up to ½ of falls among older adults can occur from trips. As such, the ability to develop an effective reactive balance response may be important in reducing falls and fall injuries. Use of a treadmill to test the response to a simulated trip usually involves high-tech kinematic analyses of the balance response. Our goal was to develop a simple clinical reactive balance rating (RBR) and compare the overall rating to standard indicators of fall risk. Methods: Independent senior housing residents (n=35, mean age 82) responded to posterior treadmill perturbations of varying speed. Using video recordings, the RBR score was based on stepping characteristics and the need for support (e.g. from a spotter). RBR scores were summed over 6 treadmill trials (0 worst, 12 best) and then compared to performance on mobility tests (such as unipedal stance time) using cut-points for increased fall risk. Step kinematics as well as RBR were also correlated (Spearman rho) with the mobility tests. Results: RBR scores (median 4, range 0–11) were associated significantly with step kinematics (rho 0.19–0.55), were generally more strongly associated (rho 0.43–0.51) with the mobility tests than step kinematics (rho 0.01–0.48), and were 42–60% lower in those at higher fall risk on the mobility tests (all p<0.04). Conclusion: Reactive balance rating after trip-like postural perturbations may provide a low-tech, valid measure to assess reactive balance kinematics, and thereby an indicator of fall risk.