Left thoracic scoliosis configurations. Why so different?

Abstract

Patients in the scoliosis screening database were analyzed with respect to curve convexity, severity, and outcome, using standard statistical methods. This study assessed whether left thoracic scoliosis is always pathologic and inquired why this is the case. Left thoracic scoliosis is more significant than the usual right thoracic pattern, but evidence in the literature is circumstantial. Prospectively collected data from 1979-1990 was analyzed in the natural history database of the school screening program. Right thoracic pattern was observed in 421 girls, and left thoracic pattern was present in 125 girls. The minimum age at diagnosis was 10 years and the Cobb angle was > 4 degrees. Primary left thoracic patterns were statistically smaller and less progressive. The left pattern of scoliosis in the absence of overt neuropathology carries a benign prognosis. This contradictory observation is examined in the light of biological asymmetry.