According to Dr. Johan Bellemans, Professor in the Department of Orthopaedic Surgery at the Catholic University of Leuven (KUL), even the expert surgeons tend to make miscalculations of two to three millimetres on average when performing artificial knee joint replacements. Dr. Bellemans, who has been involved in the development of the new robot, stated that the mistakes result in a bending distortion of up to a few degrees which causes the prosthesis' durability to be reduced with several years. With the support of the pioneering CASPAR technology, the surgeon performs the operation virtually by means of 3D visualisation on screen. The aim is to immediately assess whether the prosthesis is well placed in order to programme the robot with a precision of tenth of millimetres.
In the operating theatre, the computer disk with the pre-operative 3D patient data and planned intervention is inserted into the robot. The precision and accuracy deployed by the robot surpasses the quality of the surgeon's hands and eyes, as Dr. Bellemans explained. In contrast with conventional surgery, the patient can be sure that the matching between prosthesis and bone will be optimal. The surface-contact is maximised. The patient will recover faster and suffer less pain thanks to a stable integration of the artificial knee joint with the bone tissue. The average hospital stay will be reduced substantially while the patient will regain his mobility in no time. Dr. Bellemans equally expects the patient to be needing less rehabilitation sessions.
The University Hospital Pellenberg is one of three university medical centres in the world where the CASPAR technology is currently applied. Each year, approximately 350 to 400 patients arrive at Pellenberg Hospital to have their knee replaced. These people suffer from a worn out knee joint that is caused whether by arthritis, a car accident or a sports injury. Apart from Leuven University, two German expert centres were involved in the development of CASPAR. At present, the robot is only available in Belgium and in Germany. You can find more news and details on the continuing research related to Computer-Assisted Orthopaedic Surgery at the University of Leuven in the VMW July 2000 issue.