Balance control analysis as a method for screening and identifying balance deficits.

We propose a two-step clinical evaluation procedure to identify the possible etiology and laterality of a balance deficit. Step 1 employs a minimum clinical test battery, developed in our labs, to screen for the balance deficit by examining changes to trunk sway for standard clinical stance and gait tests. Step 2 characterizes pathophysiological components in balance corrections, as well as deficits brought about by aging, using biomechanical and electromyographic (EMG) responses to multidirectional stance perturbations. This is best accomplished by delivering stance perturbations to patients standing on a support surface that is tipped in four directions: forwards to the left and right, and backwards to the left and right. This review provides an overview of the two procedures and proposes for the screening procedure a minimum clinical test battery with a score, termed the balance control index (BCI).