Trunk proprioception: Enhancement through lumbar bracing

Objectives: To examine the effects of a neoprene lumbar brace on the proprioceptive ability of subjects without pathology and to determine whether those with poorer proprioception were more affected by the brace. Study Design: Randomized 2 x 2 Latin square cross-over design. Setting: Laboratory in an educational institution. Subjects: Forty asymptomatic subjects matched by gender, age, weight, and height. Method: Blindfolded subjects performed a position matching task in which they flexed the trunk in the sagittal plane. Six positions across the range of motion were examined. Angular data were recorded by a lumbar motion monitor secured by straps to the subject's trunk. Main Outcome Measure: Absolute, constant, and variable errors in braced and unbraced conditions. Results: The mean absolute, constant, and variable errors were 3.6 degrees, .45 degrees, and 4.4 degrees, respectively. Absolute, constant, and variable errors were significantly decreased when wearing a brace. However, the magnitude of the decreases were small (<1.0 degrees) for all errors when wearing a brace. The high error group's absolute error improved significantly (p < .05), from 6.0 degrees when unbraced to 4.0 degrees when braced. In contrast, absolute error measurements for subjects in the low error group were unchanged, with an error of 2.0 degrees when unbraced and 2.3 degrees when braced. Conclusions: The findings suggest that a neoprene lumbar brace improves the somatosensory information received by the central nervous system and results in less error in trunk positioning. Persons with less ability to match trunk position will benefit more from wearing a neoprene brace than will those who are already adept at the task. (C) 1999 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation.