Tests of Static Balance Do Not Predict Mobility Performance Following Traumatic Brain Injury

Abstract

To investigate the extent to which different single-limb support (SLS) parameters predict mobility performance following traumatic brain injury (TBI). Seventy-one people with mobility limitations following TBI were assessed for balance and mobility performance in a human movement laboratory. Participants performed a clinical test of static balance that involved balancing in SLS on each leg with eyes open and eyes closed. Mobility performance was measured by self-selected gait speed and performance on the High Level Mobility Scale (HiMAT). Dynamic stability during walking was measured by quantifying lateral centre of mass (COM) displacement, width of base of support, and proportion of double-support stance time. Total static balance scores were strongly correlated with HiMAT scores (r=0.57, p<0.001) and lateral COM displacement (r=-0.51, p<0.001). Despite these strong correlations, however, balance scores explained only 32% of the variance in advanced mobility skills (r(2)=0.32) and 26% of the variance in lateral COM displacement (r(2)=0.26). Since mobility performance varied widely for people with similar levels of balance, SLS time was not able to predict dynamic stability during gait, self-selected gait speed, or advanced mobility skills in people with TBI.