Active robotic technologies for total knee arthroplasty

When active robotic technologies for Total Knee Arthroplasty (TKA) were introduced over 20 years ago, broad usage of robotic technology was not felt to be needed as early data suggested no clear improvement in clinical outcomes compared to conventional techniques of implantation. Only recently has there been renewed enthusiasm for use of robotic technologies for implantation.

Active robotic technology specifically refers to the use of a robot for planning and executing the surgical procedure-with surgeon guidance and control. The physical work of bone preparation is performed by a milling tool, following a cut path defined by a CT-based preoperative plan. This manuscript describes the IDE experience of the only active robotic system (ARoS) available in the US, which took place from February 2017 through December 2018.

115 patients were enrolled in an IDE study to evaluate the safety and efficacy of an ARoS for TKA. No previously described safety issues for TKA occurred. Three-dimensional accuracy of component placement used the preoperative CT plan compared to the 3-months postoperative CT scan to demonstrate accuracy of all autonomous resections to within 1.5 mm and/or 1.5 degrees. Surgical planning and execution to restore alignment along kinematic principles were used in 40 procedures and to achieve mechanical alignment in 75 procedures.

This FDA study of an active robotic approach for TKA represented the first multicenter trial and first US experience with this technology. Results demonstrated an excellent safety profile and high degree of accuracy. Advantages of this approach relate to standardization of the technique, multiple device options in the implant library, an excellent safety and accuracy profile, and consistency of results. Active robotics for TKA represents a viable and safe technique for primary TKA.