Scoliotic index: a comparative evaluation of methods for the measurement of scoliosis.

A new technique of measurement--Scoliotic Index(SI)--was devised to obtain more accurate determination of the spinal curvature. In comparison with previously established methods (Ferguson, Cobb), the SI is a more comprehensive and accurate representation of the scoliotic curve. It measures that the deviation of each involved vertebral segment from the vertical spinal lines with multiple points taken along the scoliotic curve. The development of this technique proved by serendipity that the Ferguson and Cobb measurements of the angle of scoliosis are reliable and comparable at all degrees of curvature.