A Better Choice for Knee Replacement Surgery

Ever since the first artificial knee joint was fashioned from glass by Boston surgeon M.N. Petersen, surgeons have known that joint replacement has been the best way to reverse the crippling effects of arthritis and other joint diseases. Over the years the evolution of the practice has been to develop safer, stronger and more biocompatible materials. But exactly duplicating the form and function of a human joint has not been without its challenges. Dr. Jan Koenig, Chief of Orthopedics at NY’s Mercy Medical Center explains. “The problem with the early replacements is we didn’t have a good way to attach the prosthesis to the bone, and we couldn’t get the accuracy we can today. In 1972 true modern knee replacement was started it was the first time we replaced the patella, the knee cap bone, the distal femur and the proximal tibia, we put three parts into the knee, and it became a real total knee replacement.”

And while today total knee replacements are done almost as a mater of routine with a high degree of success, bringing renewed mobility to countless numbers of patients – the procedure is still not perfect. Recent studies have shown that the reason why many surgeries fail, is not because of the quality or manufacture of the implanted device, but because of misalignment of the joint during the surgical procedure. Surgeons report that misalignment using traditional techniques is a common outcome. The ability to line up the prosthesis right between the hip and ankle is very important, and it turns out that the window is very narrow, only 3 degrees. If the prosthesis is situated within a 3-degree mark chances are that implant will last a long time. If it is “misaligned or outside that three degrees, chances are that it will fail and loosen and become painful for the patient. When this occurs another procedure is often required to get rid of that pain and then make their limb nice and straight.

But the need for such re-operations is changing, thanks to a unique surgical navigation platform being used by Dr. Koenig and other surgeons across the nation. The system is called the PiGalileo and was developed by Plus Orthopedics. It employs 3-D computer mapping and micro-robotics to provide the surgeon with a degree of accuracy for aligning the implant not possible with the naked eye. This computer assisted surgery technology has been shown to be precise to within minuscule fractions of a millimeter and is completely under the surgeon’s control at all times. The system also provides valuable intra-operative feedback in real time to the surgeon – improving precision, and leading to better implant alignment and positioning.

According to Dr. Koenig, “The Key to a successful total knee replacement is to have accuracy and we know if we are accurate within 3 degrees of a mechanical axis we’ll have a longer lasting prosthesis. Years ago when we were doing conventional knee replacement the best surgeons were being 70-75% accurate. And that’s the best in the country. Now with the early generation computers, we were getting 90% accuracy. But when I utilize the mini robot, that’s getting to an accuracy rate of 99.6% and that’s pretty darn good.” Knee replacement patient Tom Ruckert was one of the first to benefit form the new technique. “I do know medically, I know my knee was in pretty bad condition, arthritis, bone spurs, problems with the knee cap, stretched ligaments. It was kind of a pot porrie of things that could go wrong with your knee. But I do not have any of that now, and that’s the amazing thing. I have a knee that will outlive me. It seems to be in perfect position, and Dr. Koenig says its is and I believe him, yeah that system made my knee 100% better.”

Currently this surgical navigation platform has been approved only for total knee replacement surgery. However understanding that 3-D visualization and micro robotics are advantageous in any procedure where precise accuracy is critical to patient safety and better outcomes, it is logical to expect that these techniques will soon be in use throughout the field of orthopedic surgery. Clinical trials are already underway for hip and shoulder replacements using similar technologies. Most surgeons agree that this an exciting time, the dawn of a new era in orthopedics, one that could not come soon enough with an aging baby-boomer population. Says Dr. Koenig; “You know the baby boom generation is coming of age now. They’re getting arthritis at a much younger age. We are seeing many people in their 30’s and 40’s who have burnt out their joints and have arthritis. They cant live this way, they can’t function this way. Now with the PiGalileo System I can guarantee them an excellent result, and more precise surgery and a safer operation. What we are looking for in longevity in the implants and the baby boomer wants to get back to doing their sports activities, golf, tennis, bicycle riding and traveling. Using the PiGalileo system they can obtain this quicker, they can also go back to work and that’s an important part of their lives.”

Arthritis and joint diseases continue to take their toll on society, however the latest advances in implants and surgical techniques are keeping both the patient, and the field of orthopedics, “on the move”.