Coordinated control of bone cutting for a CT-free navigation robotic system in total knee arthroplasty.

Background Robots are gradually becoming intelligent tools for surgeons in computer assisted orthopedic surgery. A hands-on robot combining CT-free navigation software and coordinated control has been designed for total knee arthroplasty. Methods The hands-on robot is under bilateral force control so that the robot not only follows the force commands from the operator but also shapes the reflected force back to the operator. The proposed coordinated control also defines three operating modes to fulfill intelligent bone cutting by tuning appropriate scaling to the admittance gains. Results Experimental results demonstrated assistive, resistant and emergent actions to meet various bone cutting conditions by the coordinated controller. Conclusions The proposed coordinated controller enables the robot to perform bone cutting more safely, rapidly and accurately compared with being performed by manual bone saw. The intelligent bone cutting has been successfully verified by a cadaver test. Copyright © 2013 John Wiley & Sons, Ltd.