Correlation between Hump Dimensions and Curve Severity in Idiopathic Scoliosis before and after Conservative Treatment

Study Design. Prospective study in 150 consecutive outpatients affected by adolescent idiopathic scoliosis (AIS). Objectives. The purposes were to (1) identify a correlation between hump dimensions and the severity of scoliotic curve, and (2) evaluate how the treatment influenced the main parameters of scoliosis. Summary of Background Data. The existence of a relationship between clinical deformities and curve severity in AIS is still debated. Furthemore, only a few studies have investigated the effectiveness of conservative treatment for idiopathic scoliosis taking into account both clinical and radiologic factors. Methods. 150 consecutive outpatients (mean age 12.8 ± 1.9 years) affected by AIS were subjected to conservative brace-based treatment. 134 participants completed the treatment protocol. Two parameters were considered to evaluate the treatment progress: the hump and the Cobb angle. Measurements were determined at the beginning and the end of treatment. Statistical analyses were performed in the whole sample and after dividing the study participants into 4 subgroups: patients with lumbar (n = 66) or thoracic curves (n = 68), patients ranging in age between 6 and 13 years (n = 89) and patients ≥ 14 years of age (n = 45). Results. A positive correlation was detected between the hump dimension and curve severity at the beginning and the end of treatment, except for lumbar curves at baseline. The deformity was effectively corrected by the orthotic treatment (Cobb angle: 29.4 ± 8.5° at baseline and 19.3 ± 9.8° at the end of treatment; hump severity: 11.6 ± 5.6 mm at baseline and 6.2 ± 4.6 mm at the end). In addition, our data indicate that the hump correction is more evident than that of the curve registered in Cobb degrees. Conclusion. A significant correlation exists between the hump dimension and curve severity both at the beginning and the end of treatment, except for lumbar curves at baseline. The brace treatment confirmed its effectiveness in arresting the deformity progression and inducing a remodeling both of the scoliotic curve and the hump.