Computer-assisted (CAS) joint replacement surgery uses special trackers that are attached to parts 

of the bone. The trackers are detected by an infrared camera that is connected to a computer. 

The computer then generates a ʻvirtual model of the extremity in real time. 

The computer assists in guiding the placement of the implants and assists with positioning and correct alignment of the joint replacement.  One of the most critical aspects of a joint replacement surgery is to ensure proper positioning of the implant. A misaligned implant can lead to early wear, loosening, and persistent pain. Similar to the alignment of the wheels on your car, a poorly aligned joint replacement will cause problems with early wear. 

Standard referencing instruments confirm the position of the hip or knee implant, however, the 

computer provides an additional state of the art, real-time confirmation.