In a study published in the journal Spine, researchers found that the effects of wearing a scoliosis brace for six months did not have a negative effect on gait, but did not reduce the biomechanical energy costs in patients with adolescent idiopathic scoliosis (AIS), energy costs which were shown to be 30 percent above those of adolescents without AIS.
The researchers pointed to an earlier study that showed “subtle” biomechanical changes in the gait of unbraced AIS patients, including a reduction of pelvic, hip, knee, and ankle displacements, and yet that the timing activity of the lumbopelvic muscles increased bilaterally during gait and correlated to excessive oxygen consumption when compared with healthy subjects. Thirteen girls diagnosed with AIS with left thoracolumbar/lumbar curves of 25-40 degrees participated in a radiographic and instrumented gait analysis, including assessment of kinematics, mechanics, electromyography (EMG), and the energetics of walking to assess the stiffening effects of a six-month period of brace wearing on level walking.
The participants were tested prior to being fit with a brace and again after six months of treatment, where they were tested without the orthosis. According to the study, thoracolumbar/lumbar curves remained corrected (reduced by 25 percent), apical rotation remained reduced by 61 percent, and frontal pelvis and hip motions were significantly increased during gait.
When compared with 13 girls without scoliosis, the gait parameters showed that muscular mechanical work increased, nearer to that of the healthy subjects. Bilateral lumbopelvic muscles were nearly 40 percent more active in the girls with AIS prior to brace fitting when compared with healthy subjects and did not change post-bracing except for the erector spinae muscles’ EMG activity, which decreased significantly, without any beneficial change in the energy cost of walking. The increased frontal pelvis and hip motion contributed to the improvement of muscular mechanical work during walking, according to the study.