The thoracic kyphosis angles of 16 normal individuals, 10 patients with Scheuermann's disease and 11 with adolescent idiopathic scoliosis were measured both radiographically and from Integrated Shape Imaging System (ISIS) scans obtained by surface stereophotogrammetry. There was a high correlation between the two measures. The method of kyphosis measurement from ISIS scans was then used for 30 patients with adolescent idiopathic scoliosis who underwent corrective surgery. A significant reduction in thoracic kyphosis was observed postoperatively. In another group of 28 patients managed conservatively by bracing, some hypokyphosis developed after treatment. However, we found no association between hypokyphosis and curve progression.