Knee for females is still a sore subject

Debate about whether an artificial knee implant designed specifically for women has scientific merit continues a year after the device was launched, even as the orthopedics manufacturer racks up better-than-expected sales.

Many orthopedic surgeons say Zimmer Holdings Inc.’s female knee is a marketing gimmick, but admit that they will implant them on request.

“I don’t want to have an argument with the patient over it,” said one orthopedist who asked not to be named, noting that the product is about twice as expensive as other artificial knees.

J. Raymond Elliott, Zimmer’s chairman and chief executive, said the female knee, called Gender Solutions, has been a bigger success than he had hoped, fueling a 23% earnings increase in the company’s fourth quarter.

Zimmer says its female knee implant -- shaped more like a woman’s knee, as well as usually although not always smaller than a man’s -- fits better and therefore functions better.

The Warsaw, Ind.-based company, the largest maker of reconstructive joints, is poised to roll out a new female hip by year’s end. Elliott declined to provide sales projections, but said he expected similar success.

“It’s good marketing. That’s not a sin, is it? It’s supported by science,” Elliott said during a meeting of the American Academy of Orthopaedic Surgeons this week in San Diego.

Women receive around 60% of all knee implants, and because they live longer and are more likely to become obese than men, they are expected to continue to drive the implant business.

Zimmer isn’t the only company marketing to women. Kalamazoo, Mich.-based Stryker Corp. introduced its Triathlon knee two years ago and has marketed it to women because it is smaller than its other knee implants, but has said that it also is appropriate for smaller men.

Others in the industry remain divided on the approach. Smith & Nephew, Britain’s biggest orthopedic device maker, will not be making or marketing a knee for women, Vice President Todd Durniak said.

Arlington, Texas-based Wright Medical, for its part, is awaiting Food and Drug Administration approval for a stature-specific knee, which is based on a person’s size.