Fig. 7

Automatic identification of ligament attachment areas on a vertebra using plane-based segmentation. The central point \(O\) serves as the origin for spherical coordinates, with normal vectors \({N}_{1}\) to \({N}_{9}\) defining the orientation of planes (Plane 1 to Plane 9). Each plane divides the vertebral geometry into regions, with points on one side of the plane selected as ligament attachment areas.