The effects of load carriage and bracing on the balance of schoolgirls with adolescent idiopathic scoliosis.

The balance function of children is known to be affected by carriage of a school backpack. Children with adolescent idiopathic scoliosis (AIS) tend to show poorer balance performance, and are typically treated by bracing, which further affects balance. The objective of this study is to examine the combined effects of school backpack carriage and bracing on girls with AIS. A force platform was used to record center of pressure (COP) motion in 20 schoolgirls undergoing thoraco-lumbar-sacral orthosis (TLSO brace) treatment for AIS. COP data were recorded with and without brace while carrying a backpack loaded at 0, 7.5, 10, 12.5 and 15% of the participant's bodyweight (BW). Ten participants stood on a solid base and ten stood on a foam base, while all participants kept their eyes closed throughout. Sway parameters were analyzed by repeated measures ANOVA. No effect of bracing was found for the participants standing on the solid base, but wearing the brace significantly increased the sway area, displacement and medio-lateral amplitude in the participants standing on the foam base. The medio-lateral sway amplitude of participants standing on the solid base significantly increased with backpack load, whereas significant increases in antero-posterior sway amplitude, sway path length, sway area per second and short term diffusion coefficient were found in participants standing on the foam base. The poorer balance performance exhibited by participants with AIS when visual and somatosensory input is challenged appears to be exacerbated by wearing a TLSO brace, but no interactive effect between bracing and backpack loading was found.