Till 1995 the aetiology of idiopathic scoliosis was no found and treatment by extension exercises was the most common method of therapy. The observation about scoliosis are finished in 2007 – T. Karski. On basis of ours observations (1985 – 2014) we can underlined that all extension exercises, other name - strengthening exercises, were and still are - wrong and harmful. All patients coming to our Department after such previous therapy suffered from huge deformities, bigger humps and stiffness of the spine. To explain these undesirable results of the treatment the term “the natural history of scoliosis” was coined. We studied that all strengthened exercises other name extensions exercises, in prone position exercises, “muscle corset” making exercises, were only bad, making huge iatrogenic deformity of spine and trunk.