Sometimes size does matter, especially when it comes to total knee replacements. Until now, patients in the U.S. have had to be content with a small selection of standard sized knee implants.
Now, a late-stage orthopedics startup wants to change the landscape by adding personalization and customization to the mix. ConforMIS Inc., based in Burlington, Massachusetts, has developed what it describes as the first and only U.S. Food and Drug Administration-approved custom total knee implant system where both the implant and the cutting tools required to perform the surgery are tailored to each individual. It is known as the iTotal CR Knee Replacement System. “Instead of asking orthopedic surgeons to pick six to 10 standard sizes to fit all different patients they see, every implant that we make is designed to fit you,” said Jong Lee, senior vice president of marketing and business strategy at ConforMIS.
Lee explained that the big names in the orthopedic world — the likes of Zimmer, Stryker — also do some customization in that they make the cutting guides or the instrumentation required during surgery tailored to the anatomy of the patient. However, the implant itself is still off the shelf. “We think that’s actually working on the narrow portion of the clinical benefit,” Lee said. “The real clinical benefit can come in the fact that the design approach for the actual implant [is customized] and not just on how you do the implantation or try to provide tools that improves the technique.”
ConforMIS, which has raised more than $200 million including a $89 million series E round in January, aims to take market share away from Zimmer, Stryker and other established orthopedic companies by highlighting the benefits of the system. There are several clinical benefits to having an implant that is tailored for each individual patient, agreed Dr. Terry Clyburn, an orthopedic surgeon and professor of orthopaedics at the University of Texas at Houston. Dr. Clyburn has used ConforMIS implants on roughly 44 surgeries and they are performing as expected.
“Patients recover more quickly, move more easily, get their range of motion more quickly, have less pain, get out of the hospital a little more quickly,” he said in a recent interview “We certainly don’t have long-term results, yet. [But] we know that the alignment of the leg is good and we know from history that if the alignment is extremely good, then the longevity or the lifetime of that implant is going to be better than if the alignment were bad.” But not all patients are candidates for the ConforMIS system — if they are extremely bowlegged, or cannot straighten their knee, the ConforMIS implant is not appropriate, he said.
For those that can use the system, how does it work? A doctor orders a detailed CT scan of a patient’s knee and leg, and that information is sent electronically to ConforMIS. The company uses its iFit technology to develop the implant and the cutting guides, and sends it back to the surgeon’s office. A patient undergoing total knee replacement using ConforMIS’s implant has to wait six to seven weeks for the implant to be ready.
That is much longer than the three-week wait for an off-the-shelf implant with customized instrumentation and only a week if you do a 100 percent off-the-shelf total knee implant. Clyburn, who owns stock in ConforMIS for being a consultant during the iTotal’s development and has received compensation for holding teaching labs and giving lectures, said that a patient has to wait roughly six to seven weeks for the ConforMIS implant.
But he tells patients the wait is worth it for a ConforMIS implant. “If you came to me and I was a boot company, and you said ‘I need a pair of boots night and day for the rest of my life’ and I said ‘Well, you can take an off-the-shelf pair or you could get a custom pair of boots,’ which do you want to choose?”
By - Arundhati Parmar