The iDuo G2, from ConforMIS, targets only the diseased portions of the knee.

Tissue and bone preservation has become a big deal in orthopaedics. When ConforMIS Inc. came out with technologies that not only precisely fit patients but also avoided removing bone, it was praised for its innovation. Although the company continues to improve its products, John Slamin, senior vice president of knee implant engineering at ConforMIS Inc., is hoping that bicompartmental knees will also put a dent in the total knee replacement (TKR) market within the next five years.

“The survivorship of total knee [replacements] is extremely good,” says Slamin. Good survivorship means that an implant remains functional for a long period of time. “What has emerged is that patients are not as happy with their total knee as the surgeons are with the result of the total knee. Reason being, the total knees don’t feel like a natural knee.” TKRs involve removing the anterior cruciate ligament (ACL) and can result in a less natural shape.

In an effort to resolve this issue, ConforMIS developed its iDuo bicompartmental knee two years ago and has just released the second generation of the device, the iDuo G2. In terms of user friendliness, the product is a huge leap forward compared to its predecessor. The device has an engineered patellofemoral joint to correct deformity, a more precise fit, and streamlined instrumentation that enables a faster surgical technique. In addition, a surgeon only needs to reset one-third as much bone compared to a total knee replacement (TKR).

The iDuo G2 also competes with a portion of the total knee market, says Slamin. It addresses about one-third of the patients who have a TKR but actually only suffer from bicompartmental disease (meaning two out of the three compartments of the knees are diseased).  “Over time, I think there’s a big revolution going on in the knee industry regarding bicompartmental knee replacement,” Slamin told OrthoTec. He believes that many total knee surgeons will turn to the iDuo G2 for its speed and efficiency in the operating room. The new device will also benefit patients who are demanding more conservative methods that remove less bone, have shorter recovery times, and lead to better clinical outcomes versus TKRs.

Bicompartmental disease of the knee.

The company is converting its existing G1 customer base to the new product and doesn’t expect to see further demand for the first generation of the implant. “We’re very different compared to many other device companies. Everything we make is a made-to-order, patient-specific implant; we have no inventory sitting around of the G1,” says Slamin. “This gives our sales force the opportunity to knock on the doors of either customers that weren’t interested in the earlier product or new total knee customers who should give this a second look or give it a new look [if they] haven’t seen it before.” The G2 is available in the United States and Europe. 

ConforMIS began improving the first generation of its bicompartmental knee more than a year ago. With product lifecycles occurring in approximately two-year periods, Slamin already knows how part of the third generation of the iDuo will look.

So what could possibly be next for a company that is already ahead of the game in patient-specific implants? Slamin says the worst kept secret in the market right now is the potential release of a total knee by ConforMIS in 2011. There are an estimated 600,000 to 700,000 total knee replacements annually. “If a company wants to grow, you have to get into the big piece of the pie, right?” says Slamin.