A system for video based registration between images during a skeletal medical procedure includes a stereoscopic camera, a two dimensional image detector and a registration processor. The camera is associated with a stereoscopic coordinate system, the camera acquires a stereoscopic image pair of fiducial marks fixed onto a skeletal structure. Fiducial representations of the fiducial marks appear on the stereoscopic image pair, and a skeletal representation of the skeletal structure appears on two different 2D images. The registration processor registers a stereoscopic coordinate system with a 3D coordinate system associated with a volumetric image detector, and superimposes 3D information on at least one volumetric image. The registration processor registers the stereoscopic coordinate system with the 3D coordinate system by registering the stereoscopic coordinate system with the 2D coordinate system and by registering the 2D coordinate system with the 3D coordinate system.
