A non-randomized clinical trial to assess the impact of nonrigid, inelastic corsets on spine function in low back pain participants and asymptomatic controls

Abstract

Background contextAlthough previous studies suggest braces/corsets can reduce acute pain, no prior study has assessed back function after bracing with both self-reported and objective measures. Use of both self-reported and objective measures of spine function together may be important given evidence they assess unique aspects of function. PurposeThe aim was to assess both self-reported and objective measures of spinal function before, and after, use of a nonrigid, inelastic lumbar brace. Study design/settingThis was a non-randomized clinical trial. Patient sampleThe sample included acute low back pain (LBP) participants and asymptomatic controls. Outcome measuresOswestry Disability Index (ODI), spinal stiffness, and muscle endurance were the outcome measures. MethodsThree groups were studied: −LBP/−Brace (n=19), −LBP/+Brace (n=18), and +LBP/+Brace (n=17). Both groups of braced participants were instructed to wear the brace continually for 2 weeks with the exception of bedroom and bathroom activities. Before and after the 2-week period, three measures of spinal function were performed: spinal stiffness via motorized indentation of the L3 spinous process, a modified Sorensen test (timed lumbar extension against gravity), and the ODI. Repeated measures analyses of variance were conducted for all three outcomes. ResultsAmong the groups, ODI scores decreased significantly for the +LBP/+Brace group (p<.001) compared with the other two groups. The +LBP/+Brace mean ODI score decreased 3.71 points (95% confidence interval [CI] 2.01–5.40) compared with the −LBP/−Brace group and decreased 3.48 points (95% CI 1.77–5.20) compared with the −LBP/+Brace group. Change scores for the Sorensen test were significantly increased in the +LBP/+Brace group (p=.037) compared with the −LBP/−Brace group (22.47s 95% CI 8.14–36.80). Spinal stiffness did not change significantly between groups. ConclusionsThis study demonstrates that lumbar function assessed by self-reported and objective measures does not worsen when nonrigid, inelastic bracing is used for short periods of time for those with, or without, back pain. These data add to the existing literature that suggests short-term use of nonrigid, inelastic bracing for acute LBP does not decrease spinal function when measured separately with subjective or objective tools.