Left thoracic curve patterns and their association with disease

Study Design. Analysis of clinical database material collected prospectively. Objective. Examination of the association between lateralization of scoliotic curves and the existence of underlying disease. Summary of Background Data. It has been suggested that left thoracic scoliosis configurations are intrinsically pathologic, whereas the more usual right curve is, in a sense, "normal." Methods. Research-based records were analyzed. Scoliosis configuration, patient gender, and diagnostic group were correlated. The results were interpreted within a biologic framework. Results. Congenital and infantile idiopathic scoliosis showed a random right-left curve distribution. In older age groups, boys were more likely to have a left thoracic curve and to have underlying disease, but there was no association between the two. In girls, occurrence in childhood itself and left thoracic patterns within that group were associated with disease. Nevertheless, most curves were in the right thoracic pattern, regardless of cause. Conclusions. Although an association exists between left thoracic curves and disease, it is not strong enough to determine who should be intensively investigated, to the exclusion of other clinical findings, and it seems inappropriate for a different approach to be adopted on the basis of scoliosis pattern alone. Gender in males and age at occurrence in females are more important risk factors than is scoliosis configuration. All new cases of scoliosis treated by a physician warrant equally meticulous assessment, with more sophisticated investigative techniques where indicated by the complete clinical picture, of which curve lateralization is only a part. Biologic theories of left and right are more capable of dealing with the phenomenon of scoliosis lateralization than are simple mechanics or concepts of specific diseases.