A method for tracking at least one rigid object part of a rigid reference object, wherein the rigid object part can be detached or removed from the rigid reference object is provided. The method includes obtaining a patient data set of a region around the object part, attaching a first reference star in a fixed position relative to the object part situated on the reference object, detecting reference points on the reference object and ascertaining three-dimensional spatial positions of the reference points of the reference object, assigning the three-dimensional spatial positions of the reference points of the reference object to corresponding points in the patient data set, attaching a second reference star to the object part, ascertaining positional information of the second reference star and ascertaining positional information of the object part or tracking the object part based on the positional information of the second reference star.