If you have a cavity in one tooth, your dentist is highly unlikely to remove all your teeth. Only that one cavity gets filled.

And so, for an arthritic need, why not have a knee replacement system that only replaces the two areas of the knee most commonly affected by osteoarthritis — the knee cap and medial compartment — and keeps the patient's anterior cruciate ligament (ACL) intact?

That is the comparison used by Harsh Gupta, product manager for global knee marketing at Smith & Nephew (S&N; Memphis, Tennessee), in describing the benefits of the company's new Journey Deuce Bi-Compartmental Knee System during a phone interview with Medical Device Daily. Gupta is overseeing the global launch of the Journey Deuce system.

The Journey Deuce Knee System is a new solution that could give a more minimally invasive, bone-and-ligament-preserving treatment alternative to nearly 70% of all patients receiving a total knee replacement, according to S&N.

"All the information we have says this is something that's going to do well for the patient, as well as the surgeons, because they can offer the patient more options," Gupta told MDD.

The implant is called the Deuce because it replaces only the two areas of the knee most commonly affected by osteoarthritis while keeping the third area intact. Since 2003, 1.8 million Americans have had their ACL replaced, according to S&N, leading patients to feel instability and abnormal motion in their knees.

And the Journey Deuce Knee System offers still another important benefit allowing the surgeon to keep their patients' ACLs intact, S&N said.

"The Journey Deuce Knee System is an innovative product that provides a unique option for surgeons and patients," said surgeon inventor Lindsey Rolston, MD, of Henry County Center for Orthopedic Surgery & Sports Medicine (New Castle, Indiana). "By preserving the cruciate ligaments, we would expect the Journey Deuce Knee System to feel and bend more like their normal knee than any other implant available."

Traditional total knee replacement resurfaces and replaces the ends of the thigh bone (femur), shin bone (tibia) and knee cap (patella). However, one study has indicated that up to 70% of the disease in osteoarthritic knees is limited to the knee cap and the inner portion of the thigh and shin bone (the medial compartment).

Thus, the Journey Deuce is designed to treat only those diseased areas — the kneecap and medial compartment — while leaving the lateral portion of the femur and tibia untouched.

"With the retention of the anterior and posterior cruciate ligaments, the Journey Deuce knee system addresses an unmet need in the market for the active, informed patient who may be concerned about potential reduced knee function and mobility with a total knee," said Joseph DeVivo, president of S&N Orthopaedic Reconstruction . "The Journey Deuce knee system provides a bone-conserving alternative to a total knee replacement, while allowing for earlier intervention and preserving all future surgery options for patients, including a total knee replacement."

Gupta said the company is seeing two very different groups of patients benefit from the Journey Deuce system: active knee patients who want to get back to their lifestyle quickly and who cannot take six weeks off work, as required with total knee surgery; and older patients who are not necessarily concerned about range of motion in the knee but who choose the system because of quicker rehabilitation, less pain, and less blood loss.

Exclusive to S&N, the Journey Deuce Bi-Compartmental Knee System is the only FDA-cleared knee system to replace two of the three knee compartments, the company says. The company also noted that financial analyst firm Wachovia called Journey Deuce Knee System the "most innovative reconstructive product" at this year's annual meeting of the American Academy of Orthopedic Surgeons Rosemont, Illinois) in San Diego.

It is available in Oxinium Oxidized Zirconium, S&N's exclusive bearing surface shown to reduce wear up to 85%, thereby potentially increasing the longevity of the implant, the company added.

The Journey Deuce is being launched in the U.S., Canada, Australia and Europe. Nearly 200 non-design team surgeons have been trained on the system to date, the company said.

The system is part of a family of next-generation products from S&N that aim to restore more natural motion through implants that preserve bone and ligaments or replace them with more anatomic components. Other products in the group include the Journey PFJ Patello-Femoral Replacement and the Journey BCS Bi-Cruciate Stabilized Total Knee System, which was Wachovia's pick for most innovative reconstruction product at AAOS 2006.

S&N describes Oxinium material as an advanced technology created through a proprietary process that transforms the surface to a ceramic, resulting in a material that incorporates the best features of ceramic and metal while avoiding the limitations associated with either material. It is used in the production of components of knee and hip implants that exhibits superior hardness, low-friction and resistance to roughening and abrasion, the company says.

Oxinium technology has been modeled on the company's Genesis II knee system, used in more than 500,000 surgeries worldwide. The first oxidized zirconium component was implanted in 1995. S&N reports that, since then, more than 100,000 hip and knee components have been implanted with remarkable success.

S&N specializes in orthopedic reconstruction, orthopedic trauma and clinical therapies, endoscopy and advanced wound management products.