A navigation system to track positions of surgical components during surgery of a patient. The navigation system includes a power source to emit a tracking signal during surgery of the patient, a first sensor mounted to a movable region of the patient to respond to the emitted tracking signal, and a control unit to track a position of the movable region relative to a fixed region of the patient as the movable region moves with respect to the fixed region, based on the response of the first sensor. The system can calibrated and register a movable reference point of the patient relative to a fixed reference point, and can maintain that reference point when the movable reference point moves in space during a surgical process.
