[Computer-assisted total knee arthroplasty: 12 years experience in Grenoble].

Computer-assisted total knee arthroplasty was developed in Grenoble in the mid-1990s. The first human implantation was performed on 21 January 1997, with no particular problems. Since this date more than 200,000 patients have been implanted with our device all over the world. The device is passive (not active like a robot), and requires no pre- or perioperative imaging. It is based on kinematics and palpation, the surgeon remaining in charge at all times. The computer helps to identify the lower leg axis, to accurately fix the bone cutting guides, and to check the ligament balance. These steps are not easy to perform with conventional ancillaries. The effectiveness of computer-assisted total knee replacement is well documented, although it is too early to claim that a "well-aligned" prothesis will have a better survival rate. Long-term follow-up studies are needed, with modern prostheses, to confirm the results of historical studies.