Patients are getting good results with total knee replacements (TKRs). Pain is reduced and function is improved. There are very few complications. And the final outcome is a better quality of life. As the current saying goes, What’s not to like?
As you saw in your surgeon’s office, there are, indeed, many types and sizes of implants now. Little by little, total knee implants have been improved over the years. But it hasn’t happened by magic. Makers of the implants sponsor studies to evaluate what works, what doesn’t, and what changes are needed to improve the results. Better quality of life and longer lasting implants are two main goals with total knee replacements (TKRs).
Each surgeon trains and practices new techniques before using them on patients. Like anything else, practice makes perfect. The more replacements the surgeon does, the better he or she is at that procedure. Each patient is evaluated carefully for the best implant. The size and shape of your knee are taken into consideration. Any muscle imbalances or joint alignment problems are also assessed and corrected as much as possible.
Studies to examine key features of implants are ongoing. For example, a large study comparing three design components was recently published. The focus of attention was on: 1) metal backing on the tibial portion of the implant, 2) patella resurfacing, and 3) a metal bearing between the tibia (lower leg bone) and the femur (thighbone).
Each of these design features was compared between two groups of total knee replacement patients. One group received the particular component. The other group did not. Surgeons performed the procedures according to their own standard methods. Outcomes were measured in terms of cost, effectiveness, complications, function, and quality of life. The study had a follow-up period of two years.
There were many findings from the study such as complication rate (equal among all groups), operative time (longer in the metal backed group), and hospitalization (average was nine days for all groups). In addition, 95 per cent of all patients went home directly from the hospital. Pain was reduced and function improved within the first three months. Gradual improvement continued after that initial recovery period.
But the bottom-line was that the overall results were the same from group to group. Everyone improved equally by the end of two years. Rates of complications during that time were the same and functional recovery was no different from group to group. Outcomes were measured according to results important to the patients (not the surgeons).
That’s all good news, but it doesn’t exactly answer your question. That’s because even with all their expertise, the authors of that particular study couldn’t recommend one implant over another just yet. But the hope is that with long-term results, patterns of design wear and the pros and cons of each will be more obvious. The wide range of surgical centers and techniques may have some effects on the results. These factors will be taken into consideration over time as well.