Postural and balance control in adolescents with idiopathic scoliosis : sensory inputs analysis

Details

Supervisors

Mahaudens, Philippe

Faculty

Faculté des sciences de la motricité

Degree label

Master [60] en kinésithérapie et réadaptation

Abstract

Objective: The aims of this study were to consider the relative participation of all sensory inputs together, to compare changes in dynamic postural and balance control between a healthy population and an AIS population, and to observe the effect of the severity of the scoliotic curves on these disorders. Background: Adolescent idiopathic scoliosis (AIS) is the most common form of spine deformity during growth. Previous studies have shown disorders of postural and balance control in AIS, involving dysfunction of the sensory information, i.e. either proprioceptive, either vestibular, or either visual systems. Materials and methods: A control group of 56 nonscoliotic subjects and an AIS group of 60 scoliotic patients, divided in three subgroups according to the value of their Cobb’s angle (group ≤20°, group 20-40°, group ≥40°) were compared for this study. The Equitest system, which is a computerized dynamic posturography technique, was used to evaluate the contribution of each sensory input, i.e. visual, somatosensory and vestibular information, while maintaining balance. Only the sensory organization tests (SOT) were analyzed in this study. Results: No significant differences were found between control group and all three AIS subgroups for the equilibrium score, although, in all groups, a general tendency of decreased scores was observed when conditions got more difficult. For the strategy analysis, only scoliotic subgroup ≤20° showed more hip strategy compared to control group, when vestibular input was the only available information (condition 5). Finally, the center of gravity (COG) in the mediolateral plane when first vision (condition 3) and then proprioception (condition 4) were altered , differed for scoliotic subgroup ≥40° compared to other groups, showing a COG more deported to the left of the midline. Conclusion: In this study, the results between scoliotic patients and healthy subjects are almost all insignificantly different, enabling us to conclude from these results that the responses of the somatosensory, visual, and vestibular inputs do not differ between healthy adolescents and AIS adolescents. Moreover, the lack of significant differences between each AIS subgroups show that the severity of the scoliotic curve has no impact on postural and balance disorders in AIS. Further studies are needed to observe if the type of curve or the side of the curve convexity influence postural and balance control when sensory inputs are altered.