Derry surgeon says replacement knees made with 3-D technology cut surgery, rehab time | New Hampshire
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Derry surgeon says replacement knees made with 3-D technology cut surgery, rehab time

New Hampshire Union Leader

June 13. 2017 3:32AM
Dr. Thomas Marks holds a replacement knee joint custom-made using 3-D modeling technology, at his office at Rockingham Orthopaedic Associates in Derry. (THOMAS ROY/UNION LEADER)
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Esther Cohen of Salem knows the pain of arthritis all too well. She’s got it in her hands and in her knees.

She takes medication that helps, and she also participates in exercise classes at the Ingham Senior Center a few times a week. The exercise eases the “gnawing pain,” especially in her knees.

“If I don’t come, I notice a difference,” she said.

Nearly half of all Americans develop knee osteoarthritis in at least one knee in their lifetime. Exercise is a key component in helping a patient, but a knee replacement provides the best course of relief, according to the American Academy of Orthopaedic Surgeons.

It’s not an easy surgery, but with advancements in 3-D technology, people can have their knees replaced in a fraction of the time, experience full range of motion and put their full weight on the joint within hours of the procedure, said Dr. Thomas Marks of Rockingham Orthopaedic Associates in Derry.

He says the 3-D technique is revolutionary and comes with a rapid recovery time, reduced risks with surgery, less pain medication, and the custom fit of the prosthetic provides immediate relief.

With traditional replacements, Marks said, the prosthetics used are standardized with sizes based on 80 percent of the population.

“So it’s not an exact fit; it’s a close fit,” he said.

Now his patients are getting custom fit. A 3-D CT scan is done of the knee, the scans are then used to print a 3-D model of the knee and a new one is built from the model.

Marks said it arrives in one piece in a “simple box,” where a traditional replacement knee comes in pieces on 17 different trays and each piece has to be washed and sterilized before being used.

Because it’s one piece, Marks said he doesn’t have to cut ligaments or tendons meaning less blood loss and less swelling. As a result, he said, most of his patients are up and walking with full range of motion and putting full weight on their knee in a matter of hours.

“I actually have to slow people down because they feel so good,” he said.

Shirley Ann Shaw-Baroffio (foreground) works out at a Arthritis Exercise class at the Ingham Senior Center in Salem on Friday. (DAVID LANE/UNION LEADER)

Marks said his patients still spend one night in the hospital after surgery (a traditional knee replacement requires two), but he’s close to offering the procedure on an outpatient basis. 

“I am having patients even in their 80s and 90s leave the next morning,” he said.

With insurance, the customized prosthetic does not cost the patient any more than a traditional replacement knee, but Marks said that there is a potential savings per patient.

Marks said he was set to retire two years ago when he learned of the new procedure being done by a colleague. He said it “got me back in the game.”

Marks said with the 3-D technology he can perform four or five of these surgeries a day, as opposed to two traditional replacements.

An estimated 600,000 knee replacements are performed in the United States each year, a number which is expected to jump to 3.5 million a year by 2030, according to the American Academy of Orthopaedic Surgeons.

Health Derry