Karthikeyan E. Ponnusamy, MD, and S. Raymond Golish, MD, PhD
Robotic assistance is a relatively new technology for unicompartmental (UKA) and total knee arthroplasty (TKA), as well as for certain aspects of total hip arthroplasty (THA). Currently, two systems have been approved by the U.S. Food and Drug Administration (FDA) and are commercially available in the United States—RIO® (MAKO Surgical, now owned by Stryker Corp.) and ROBODOC® (Curexo Technology).
The hypothesis and rationale for such systems is that robotic assistance may result in improved component positioning and alignment that influences long-term clinical outcomes. According to reports for TKA, for example, conventional surgery achieves neutral alignment (within 3° of the mechanical axis) only 75 percent of the time, and coronal suboptimal alignment greater than 3° correlates with worse outcomes. In the case of UKA, robotics may aid component alignment and fixation within the limited surgical exposure.