Computer- and robot-assisted total knee replacement: analysis of a new surgical procedure

This paper describes a nonstandard procedure for total knee replacement (TKR), based on the use of modern tools such as computers, electronic sensors, and robots, to achieve accurate and optimal implant results. The intervention is planned on a standard PC connected to the CT scanner. Dedicated software shows the surgeon limb alignment and knee status and assists in the choice of the best prosthesis. The intervention is then performed with a new device and surgical procedure. At first the femur and the tibia are fixed to the operating table with a special clamp and the knee bones are exposed with the standard technique; then the surgeon digitizes the shape of the joint and the computer transfers the planned surgical strategy to a dedicated surgical robot. Resections are performed by the surgeon on a constrained guide held by the robot. In this paper we summarize the main results on the system performances, and discuss the clinical implications of this new technology in the operating room. Preliminary experiments on cadavers and volunteers show that this methodology can improve the accuracy of the implant to 2.5 mm and 20, reduce operating time and surgical errors, and may represent a challenging alternative methodology for TKR.