Subjective visual vertical in patients with idiopatic scoliosis

Idiopathic scoliosis (IS) is characterized by a three-dimensional deviation of the vertebral column and its etiopathogenesis is unknown. Various factors are associated with idiopathic scoliosis, among these a prominent role has been attributed to integration of vestibular information with graviception for perception of space. Subjective visual vertical (SVV) is a sensitive sign of verticality perception. The aim of this study was to determine if SVV in adolescents with IS is different from healthy controls. Examination of SVV was performed using the bucket method. Binocular measurements of SVV were made in 23 adolescents with IS (age 14.5 ± 2.5, mean ± SD) and 23 healthy subjects (age 14.0 ± 2.9). The groups differed significantly on SVV deviation (p < 0.01): healthy controls (-0.04° ± 0.64°), IS group (0.86° ± 1.39°). There was also significant difference in SVV uncertainty (p< 0.001): healthy controls (1.50° ± 0.94°), IS group (2.46 ± 0.82°). We conclude that the perception of visual vertical is altered in IS which may play role in development of IS.