Patent attributes
A system for registering an orthopedic implant in a computer assisted navigation system. The system includes a plurality of differently sized implants which may be the femoral component or hip stem of a prosthetic hip joint. A registration device is engageable with each of the implants in a predefined relative position. The registration device also includes at least one reference element registerable in the computer assisted navigation system. A second reference structure also having at least one reference element registerable in the computer assisted navigation system is detachably secured to the implant. The relative positions of the reference elements located on the registration device and second reference structure differs for each of the plurality of implants and thereby allows the navigation system to determine the nominal size of the implant. The relative position and orientation of the implant relative to the second structure can also be calibrated using the registration device.