JIP: The etiology of scoliosis

Twenty years ago the late John Cobb first showed me that scoliosis could be interesting. By the very simplicity of his teaching he changed an obscure, incomprehensible deformity into a disease which has fascinated me ever since. I recall gratefully his ability to make the complex simple. I propose to look at this deformity in all its forms, to name the questions one must ask and answer if its etiology is to be established. At the end of this you will not know the etiology of scoliosis, for I do not myself, but it is my hope that you will comprehend the problem better. Although idiopathic scoliosis because of its frequency, its severity and the mystery of its origin is the main problem, it is important to look at scoliosis from all causes. Scoliosis is a deformity that may be caused by many diseases, and though in some the mechanism may be clear-as for example in congenital scoliosis-in most it is wholly beyond our understanding. After poliomyelitis, limb deformity occurs in children left with muscle imbalance while still growing; trunk muscle imbalance likewise causes paralytic scoliosis. Knowing this has singularly failed to help us to understand idiopathic scoliosis; children with idiopathic curves do not have muscle imbalance. Although there are differences between paralytic and idiopathi