Stereophotogrammetry in the evaluation of the treatment of scoliosis.

A previously existing X-ray stereophotogrammetric method which allows the measurement of simultaneous changes in all components of a scoliotic deformity was developed without the use of invasive methods or skeletal markers. In order to evaluate the changes in rotation and lateral deviation of the scoliotic curve following treatment with the Boston brace, this method was applied to 31 patients suffering from idiopathic scoliosis. The derotational effect of the brace averaged 14 degrees (0-38 degrees) in 21 patients remaining after rejection of those whose radiographs were of inadequate quality. The accuracy, however, was not acceptable because of frequent gross errors due to the poor quality of the radiographs. Image interpretation may be improved by a suggested technique of enhancement based upon a computer program for figure restauration and border detection.