Bespoke Knees

Bloomberg recently announced that the Food & Drug Administration has bestowed its blessing on a new “gender-specific” knee implant. Manufactured by Smith & Nephew, the new knee is designed to fit the “unique anatomy” of a female. This is not the first knee- for- women-only. Last year the FDA approved a similar knee made by Zimmer Holdings, the company that takes credit for what it describes as a “bespoke knee” for women.

Will the new devices allow women to function better? "In theory, yes, but the evidence isn't there," Kimberly Templeton, an associate professor of orthopedic surgery at the University of Kansas Medical Center and a spokesperson for the American Academy of Orthopaedic Surgeons told U.S. New & World Report. Sheryl Conley, Zimmer's chief marketing officer explained seven studies now underway will look at patient satisfaction and range of motion. Preliminary data will be available in a year or so.

In the meantime, these couture knees for women are fetching twice as much as the plain-vanilla knees that, until recently, were used for both men and women. But this is not the FDA’s concern.

When it approves drugs and devices it doesn’t ask whether the product is cost-effective, i.e. whether it is any better than similar, less expensive products already on the market. And neither does Medicare. Once a product receives FDA approval, Medicare usually agrees to cover it (as it did in this case) and private insurers often follow Medicare’s lead. Which means that in the end, we all pay for innovative new products (whether or not they actually mark an advance in medical science) in the form of higher insurance premiums, higher Medicare co-pays, and/ or higher hospital bills. (Often Medicare’s reimbursements to hospitals that use an expensive new device not reflect the added cost, and hospitals have no choice but to shift the cost to other patients.

Which brings us to the obvious question: just how different is the new design? Is it worth the extra dollars?

According to blogger Dr. William Barrett  the new knee is both a little longer and a little narrower than conventional knee replacements—and that’s about it. And in fact, many manufacturers already offered knees that fit women perfectly well. This isn’t really about design innovation, suggests Barrett, who practices with Valley Orthopaedic Associates in Seattle, WA; it’s about marketing hype: “if we drill down and look at the data,” he explains, we can see that the [companies’] claims are not totally accurate…In general, there is a difference between the size of the male and female knee with the male knee being slightly broader in the medial/lateral direction in comparison to the female knee,” but Barrett points out that women already get smaller knee replacements anyway. “When we look at the actual implants used for the female, typically the smaller size range implants are implanted in females and the larger size implants are implanted in males. If we look at data from over 14,000 knee replacements performed at eight different centers in the United States, over 75% of females received the smallest three sizes of a particular implant line. Within these sizes, the fit for the female was ideal.”

“Less than a quarter of women had a larger sized implant”–-and in those cases, Barrett acknowledges, “some overhang of the implant is possible” because the knee is too wide. But he points out: “The company that promotes the gender-specific knee . . . had wider implants then the average orthopedic company in the marketplace. Therefore, they recognize an error in their implant design and to correct this, added more implants (my emphasis). “The reality,” he concludes, “is that most other implants fit the female knee quite well.”

In other words, Zimmer saw that their implants were too big and chose to create a new product to rectify this problem. This is what marketers call “product extension.” You take a good product, tweak it, and advertise it as the “new, new thing.” Tobacco companies have always been good at this: recall the creation of “Virgina Slims” the sexy, sassy new cigarette for women. (“You’ve come a long way baby”). Some years later, they created a new longer, thinner version of Virginia Slims. The purpose was not entirely clear: would it make your nose look shorter, your fingers look longer?

But no doubt it sold, just as knees for women have sold. According to 2007 financial reports, knee replacements are Zimmer’s fastest growing product. Reconstructive sales for the company are surpassing expectations: as of this past April, there had been more than 14,000 implantations of the Gender Solutions Knee, exceeding the company’s target of 12,000—despite the fact that the Gender Solutions knees cost about twice as much as other implants.

And no wonder. The gendered knee is backed by Zimmer’s first direct to consumer marketing campaign, noted by commentators as being a strategy attempting to “lure more women into the operating room.” The gimmick of the campaign is a duo of “Blue Ladies,” created with the help of R.O. Blechman, who is best known for his work with The New Yorker—check out a Zimmer ad incorporating his style here. With television advertising rolled out in 23 markets around the country Zimmer is spending $9.4 million on the ad campaign.

The advertisements seem to be working: the company reports that “second quarter [2007] sales significantly increased from the first quarter” and that the company will now focus on “expanding availability in Europe and Asia Pacific” while “increasing U.S. market share.” And what a market it is: Women account for almost two thirds of the 400,000 knee replacements performed annually in the US, and the number of US knee replacements is expected to soar to almost 3.5 million by 2030. Zimmer is readying a line of Gender Solutions hip implants as well. Women, we are told, like the idea of custom-made joints.

But some doctors remain skeptical of the need for a knee specially made for women. ABC News quoted Dr. William Hozack, president of the American Association of Hip and Knee Surgeons and professor of orthopedic surgery at Jefferson Medical College in Philadelphia: "What the companies are attempting to do is make knee replacements with different shapes that might better fit people (women among them) whose anatomy is slightly different. That the companies are choosing to market to women is just that -- a marketing campaign.” Dr. Kevin J. Bozic, assistant professor of orthopedic surgery and health policy at the University of California at San Francisco agrees, telling BusinessWeek that “we don’t think the incremental change in the technology justifies the cost.”

Still, Zimmer is doing all it can to make the Gender Solutions Knee a must-have for doctors and surgeons, including sponsoring webcasts of knee transplants (performed, perhaps unsurprisingly, by a doctor who “helped design” the Gender Solutions Knee). And at the end of the day, if patients want a “gender-specific” knee, doctors are likely to give it to them. This is something called consumer-driven medicine—which sounds like a good idea. But can we afford it? I’ll be talking more about this in the future.