To provide a method that automatically detects a spinal axis and a spinal boundary from an image.

A system and method for automatic detection of a spinal axis and a spinal boundary from an image scan an input image in at least two scanning directions to prepare a ridge map related to each scanning direction (16 and 18). The ridge maps are amalgamated to reinforce a projected spinal axis (20). Piecewise linear approximation is provided for the projected spinal axis (22), and a gradient map of the input image is reinforced (26) to display projected spinal boundaries in an emphasized manner. The spinal boundaries are computed by constraint of the projected spinal boundaries on each other and on the spinal axis (30).