Comparison of three lumbar orthoses using motion assessment during task performance.

Abstract

Four conditions (three orthoses, one no orthosis), full cross-over, randomized order, 12 subjects tested 3 months after a lumbar surgical arthrodesis. To assess whole torso and lumbar motions and comfort for each orthoses condition during performance of activities of daily living. Previous noninvasive studies measured whole torso (not just lumbar) movement. Recent development of a low profile, flexible, strain-gauged device ("Lordosimeter") facilitated this study. The Lordosimeter was taped to the skin along the midline of the lumbosacral region. Orthoses studied were Boston anterior opening, Aspen lumbosacral, and Cybertech. Specified activities of daily living were performed for each orthosis condition. Subject effort during the flexion/extension task was assessed by surface electromyography (EMG). Comfort was assessed by visual analog scale. There were no significant differences in EMG between orthoses. For lumbar flexion, trunk flexion, total lumbar motion, and total trunk motion, the mean values for Aspen and Boston (but not Cybertech) were significantly smaller than for no orthosis for most of the tasks and there were no significant differences between Aspen and Boston. The total lumbar motion allowed by each orthosis (averaged across tasks and relative to the no orthosis condition) was 81% for Aspen, 79% for Boston, and 97% for Cybertech. The comfort rating averaged across tasks was 2.24 for Aspen, 4.12 for Boston, and 3.92 for Cybertech (0 = very comfortable, 10 = very uncomfortable). Aspen was significantly more comfortable than Boston or Cybertech. Boston and Cybertech did not differ significantly. The Lordosimeter is useful for measuring lumbar motion during orthosis wear. The Aspen and the Boston orthoses provided significant flexion-extension motion restriction compared with no orthosis, but for almost all of the motion measures did not differ from each other. The Cybertech did not differ significantly from the no orthosis condition. The Aspen orthosis was rated significantly more comfortable than the Boston or the Cybertech.