The influence of vision and support base on balance during quiet standing in patients with adolescent idiopathic scoliosis before and after posterior spinal fusion

Abstract

Background contextScoliosis is the most common postural alteration in adolescence and is characterized by deviations of the spine in three planes. Surgical treatment based on arthrodesis has been developed, but the effects of such restructuring on the systems involved in postural control need to be better understood. PurposeTo assess the influence of vision and the support base on balance in the quiet standing position in adolescents awaiting surgical treatment for idiopathic scoliosis. Study design/settingLongitudinal study/Ribeirão Preto Clinics Hospital (HC-FMRP-USP) and Laboratory of Assessment and Rehabilitation of Equilibrium at the FMRP-USP. Patient sampleAdolescent idiopathic scoliosis patients and controls. Outcome measuresCenter of pressure (CoP) sway area of the 95% confidence ellipse. MethodsThirty female adolescents were divided into two groups according to their spinal alignment: control (n=15) and scoliosis groups (SGs) (n=15). The subjects with scoliosis were evaluated before and 7, 30, 60, and 90 days after surgery; the controls were evaluated once. The area of CoP oscillation was measured with the eyes open and closed and with two different support bases (feet apart or together). The force platform was purchased with funding support (US $8,375.00) provided by the Research Foundation of São Paulo (FAPESP). The study sponsors had no involvement in the study. Data were collected from the force platform and then statistically assessed through a linear model analysis of mixed effects. ResultsData reveal that subjects in the SG oscillated more than controls, and postsurgery subjects had more oscillation than presurgery subjects. The results also indicated that both groups (control and scoliosis) showed more oscillation among those subjects with feet apart and eyes closed, but subjects with scoliosis were more affected by vision deprivation than by a reduced support base. ConclusionsOur results indicate that adolescents with idiopathic scoliosis are more dependent on visual information and that surgical correction does not change this relationship.