Fit for Duty

Measure twice, cut once. That old carpentry adage obviously applies at least as well in the matter of medical implants, and that’s where ConforMIS comes in.

The company is using a combination of detailed imaging and rapid prototyping to make a definitive statement in the knee-replacement field. Definitive, as in what it labels “patient-specific” implants. ConforMIS says its philosophy is simple:

“Make the implant fit the patient rather than forcing the patient to fit the implant.”

Since its founding in 2004, the Burlington, Mass.-based firm clearly has differentiated itself from the very substantial competition by offering patient-specific knee resurfacing implants designed to offer osteoarthritis patients a more customized fit based on measurements obtained from a computer tomography scan.

That is a significant departure from practice. Most manufactures in the space make the implants in a variety of sizes—usually 10 or so at most—so when it comes time to put an implant into a patient, a surgeon has to do a fair amount of manipulation of the surrounding bones. But ConforMIS’ iUni fits the patient by taking imaging data from a CT scan and using the company’s iFit technology to create a custom implant, usually taking about six weeks from scan to the completed implant being in the surgeon’s hands.

ConforMIS essentially competes with every company in the replacement-knee space, including firms such as Zimmer, Stryker, Johnson & Johnson’s DePuy business, Smith & Nephew Orthopaedics and Biomet. Each is a big player in the space, and some are absolute giants.

But there’s that “patient-specific” thing. ConforMIS CEO Philipp Lang, M.D., puts it this way: “We take a completely different approach. We get the imaging data and then we make a tailor-made implant for that patient.”

The CT data is transformed into patient-specific implants and instrumentation via its iFit technology, which converts CT data into implants that are precisely sized and shaped to conform to the unique topography of each individual knee joint. The company’s iJig instrumentation uses the same data to create cutting and placement guides that the company says eliminates the need for manual sizing, reduces surgical time and trauma, and improves reproducibility.

The platforms are supported by proprietary intellectual property consisting of more than 250 patents and pending patent applications that encompass imaging software, image processing, implant design, surgical techniques and orthopedic instrumentation. While ConforMIS at present is focused on the knee, it says the technology is applicable to all major joint systems.

ConforMIS launched the latest iteration of its unicompartmental knee-resurfacing device, the iUni, in the United States late last year, with CE-mark certification coming this past April. Dubbed the iUni G2, its enhancements include an improved, wear-optimized design, instrument changes designed to make for even simpler surgical techniques, and iView patient-specific images for improved surgical planning. It is available for both medial and lateral compartment treatment.

Lang said the iUni G2 was designed with surgeon feedback playing a large role. He said the technology represents not only advances in implant characteristics, but also advances in the experience surgeons will have in the operating room.

Terry Clyburn, MD, an orthopedic surgeon in Bellaire, Texas, who performed the first iUni G2 procedure last fall, cited the “more streamlined surgical process” possible with the new system. He praised ConforMIS for listening to surgeons and providing rapid updates, saying that is “a testament to the advantages of their just-in-time model.”

In addition to the iUni for unicompartmental procedures, ConforMIS has developed the iDuo bicompartmental knee resurfacing system, which resurfaces only the affected areas of either the medial or lateral compartment of the knee plus the patellofemoral compartment, in the process preserving far more bone than in a traditional knee replacement surgery.

While it battles both industry giants and surgeons’ long-established ways of doing things, it is clear that ConforMIS has many believers. In the summer of 2009, the company reported raising its largest round of funding to date—$50 million—from private-equity and sovereign-wealth funds in the United States, Asia, Europe and the Middle East.