LAURIUM - For the first time, a surgeon at Aspirus Keweenaw Hospital has conducted a partial knee replacement in a patient using an innovative technology used in England.
Dr. Ken Pherson, DO, an orthopedic surgeon at Aspirus Keweenaw Hospital in Laurium, conducted the partial knee replacement before the holidays and said the patient is adjusting wonderfully with the reconstructed knee.
"I saw him last week," he said. "He has minimal pain and he's walking around with no assisted device and has not used one since surgery."
Dr. Ken Pherson, DO, an orthopedic surgeon at Aspirus Keweenaw Hospital in Laurium, shows how the Oxford Partial Knee Replacement works. (Houghton Daily Mining Gazette photo by Stacey Kukkonen)
The surgery, new to the hospital, is the first of its kind locally, and possibly in the Upper Peninsula, Pherson said.
As part of the surgery, the Oxford Partial Knee Replacement - a metal alloy device - is used and is implanted on the end of the thighbone and a plastic piece is used on the top of the tibia and underneath the kneecap.
"Instead of replacing the whole knee, we just do the one compartment, on the inside part of the knee," Pherson said.
Usually, that's where arthritis is developed first and the candidates are specifically selected for the procedure.
"We look at three compartments," he said. "The inside, outside and underneath the patella (kneecap)."
The patient who received the procedure had come in with knee pain, and with a knee scope it was determined he didn't have arthritis in the other compartments.
"You don't have to do a knee scope," Pherson said. "You can do X-rays."
A stress X-ray is conducted to ensure other departments don't compress and then a state-of-the-art mechanism is put in place.
If arthritis is seen in other compartments, Pherson said then circumstances change and a total knee replacement needs to be done.
"A lot of doctors do a knee scope first to assess how much arthritis there is before going in," he said.
Once in surgery, Pherson said work is done on the cartilage, which is really where the replacement takes place. The knee itself is not replaced, only the damaged cartilage and bone ends using the metal alloy Oxford Partial Knee Replacement mechanism from Biomet.
"This knee replacement has been done in Oxford, England, for almost 30 years now," he said. "It just came to the United States 10 or 12 years ago."
It's the only surgery of its type that required FDA certification to be put in place, which required Pherson to attend a training course in Arizona.
"I did probably 50 or so of these with different doctors during my residency in Chicago," he said.
The Oxford Partial Knee Replacement is the only device with a metal bearing, so when the knee moves, the bearing slides back and forth. The implant is designed to create a smooth-functioning joint to prevent bone-to-bone contact, which can be painful.
"What they found is that they get less wear," Pherson said. "Less than 2 percent of the patients that have this done go on to get a total knee replacement."
The partial knee replacements allows for a smaller incision with less pain and shorter recovery time, he said.
Pherson said he's happy he was able to bring this technology, which lasts a lifetime, to the local area.
"The components we use now ... are made so much better now, they last so much longer," he said.
"It's another option you can give a patient who has knee pain."