Systems and methods of tracking a head of a patient are provided. The system includes a motion tracking system and a head tracker. The head tracker includes a frame, at least one trackable target coupled to the frame, at least one nose pad coupled to the frame, and a pair of adjustable ear coupling members coupled to the frame and shaped for engaging with at least a portion of a back surface of an ear of the patient. The head tracker is configured to apply a clamping force to hold the trackable target in a stable spatial relationship with a location of interest in the head. The motion tracking system includes a sensor for tracking the trackable target and a processor configured for determining a position of the location of interest from the position and orientation of the trackable target and the stable spatial relationship.