Gait initiation reflects the adaptive biomechanical strategies of adolescents with idiopathic scoliosis.

BACKGROUND The dynamics behavior of patients with idiopathic scoliosis obviously requires some biomechanical compensatory strategies. Our objective is to analyze the ground reaction forces (GRF) exerted during gait initiation in order to determine the dynamic consequences of idiopathic scoliosis. METHODS Ten adolescent girls suffering from idiopathic scoliosis with a right thoracic curvature (Cobb>15°) and 15 healthy adolescents participated in this study. Two force plates were used to record the ground force evolution for the right and left limbs tested during gait initiation. RESULTS Whichever limb was used to initiate gait, gait initiation duration was found to be significantly longer in persons with scoliosis than in healthy subjects. In the scoliosis group (SG), the impulses, occurrences and forces values were also greater than in healthy subjects. Under the stance foot, the anteroposterior and vertical forces were always increased. Under the swing foot, the SG showed the same characteristics associated to decreased mediolateral impulses parameters. Even greater differences were observed between these two groups in terms of peak occurrences during left-limb gait initiation. The intragroup comparisons only unveiled very few differences between the two limbs for the control group (CG), whereas significantly higher values were recorded for the group of scoliosis patients when gait was initiated with the left limb rather than with the right one. CONCLUSION For patients with scoliosis specific dynamic behavior adjustment are made during gait initiation patterns, for both limbs in order to maintain balance during gait to compensate for their spine deformation. Patients with scoliosis always showed slower dynamic patterns than healthy controls. These results show the importance of including specific evaluation and dynamic physical rehabilitation for patients with idiopathic scoliosis.