By Laura Freeman
Since the first advances in knee replacement surgery in the 1960s and 1970s, a steady progression of innovations in techniques and technology has continued to improve the procedure and patient outcomes.
The latest step forward is the cementless version of the Oxford unicondyl implant for partial knee replacement by Zimmer Biomet which recently received approval by the FDA. After 20 years of clinical experience and more than 300,000 procedures across Europe and other regions, the new implant’s success has been impressive.
“With the cementless version, the primary advantage is that there should be less risk of the joint loosening over time. It also removes the possibility of an adverse allergic reaction or sensitivity to the cement,” said orthopedic surgeon Patrick Peavy MD of Alabama Ortho Spine and Sports. “As the incision heals, a natural bond forms with the surrounding tissue, holding the implant in place.”
The precision required for successfully performing the procedure is a bit more demanding, which is why the initial approval of the implant was granted to only 50 orthopedic surgeons in the United States. In Alabama, that surgeon was Peavy.
“My mentor in Boston was noted for his work in partial knee replacements. I became interested in this option and followed the development of the cementless version,” he said. “It was clear that the advantages were worth the additional training and precision required to perform the procedure. The cementless procedure has been available for a while in Europe and the results have been excellent. Surgeons who have been performing the technique there came to help train the first surgeons here who would be working with the cementless implant.
“I began offering the option to selected patients shortly after FDA approval was finalized. The outcomes have been very good. Patients were pleased when I explained the advantages of the cementless procedure and that it should last longer. What they really get excited about is being able to choose a partial knee replacement rather than having to undergo a total knee surgery. The partial knee procedure only removes the damaged part of the joint. It’s usually less painful and recovery tends to be faster.”
In his practice, Peavy performs both partial and total knee replacements in patients of all ages. “While it’s true that time tends to increase wear, age isn’t the only factor in determining which procedure would likely offer the best outcome for a particular patient,” he said. “Each case has to be evaluated individually based on the location and severity of the damage.
“Since accidents and sports injuries may damage only part of the knee, it follows that we would see that more in active people who tend to be younger. The partial knee surgery preserves more of the original tissue, so we get more natural movement. In addition to getting patients back to their lives faster, preserving more healthy tissue could also be an advantage in later life if the patient eventually needs a revision surgery or a full knee replacement.”
Judging by procedures in Europe, there seems to be a positive correlation between good outcomes and the frequency of experience of the surgeon using the technique, with surgeons who do 30 to 40 or more cases per year becoming particularly adept.
As with other joint replacements he performs, Peavy says prehab and rehab can be a major plus. “If patients have coverage for enough physical therapy visits per year, it would be great if they could do both,” he said. “It’s always good to go into surgery with muscles in the best possible condition and to get patients back on their feet as soon as possible afterward. And after surgery, I usually recommend looking at lower impact activities, but if a patient’s joy in life is running, I’m not going to tell them to give up what matters to them. I tell them to listen to their body. Take reasonable precautions and go enjoy life.”
