A process for confirming registration of bones involved in a joint replacement procedure is provided that includes a three dimensional (3-D) models of the bones being generated. The bones are tracked with a tracking device attached to each of the bones to allow 6-degrees of freedom (DOF) tracking during the joint replacement procedure. The 3-D models to the bones are registered and the bones having the tracking device are moved. A corresponding motion in the 3-D models with the moving of the bones is then observed. The registration of the 3-D models to the bone when the observations of the 3-D models move in correspondence with the actual bones is then confirmed or an alarm when an algorithm detects the 3-D bone models move unexpectedly during the movement of the bones. A system for confirming registration of bones involved in the joint replacement procedure is also provided.