Robotic Lateral and Medial Unicompartmental Knee Arthroplasty

Unicompartmental knee arthroplasty (UKA) for end-stage degenerative disease of the knee limited to one compartment is a viable alternative to total knee arthroplasty (TKA). UKA necessitates less bone resection and tissue disruption, reduces blood loss, and preserves cruciate ligaments. UKA can be performed in either of the 3 knee compartments with medial compartment the most common. Lateral compartment UKA is a technically difficult surgery, but robotic systems can mitigate the difficulty for surgeons. Recently, robot-assisted systems have become available for UKA that have been shown to improve accuracy of component placement and allow for intraoperative real-time dynamic ligament balancing. A 3-dimensional model of the patient's anatomy is created from a preoperative computed tomography scan of the patient's knee, which is mapped to anatomical landmarks registered intraoperatively. Components are then placed for an operative resection plan. The robot-assisted system provides haptic feedback to the surgeon during bone resection, including an alert, should the high-speed burr leave the preplanned resection area. Postoperative measures have shown superior accuracy of component accuracy with robotic systems compared with conventional UKA surgical techniques. Currently, short-term and midterm clinical outcomes of robot-assisted UKA are available that appear similar to those of conventional UKA.