In orthopaedics, it seems that every month or so, an announcement comes out about a new and innovative technology. Whether these technologies are, in fact, new and innovative may be debatable, but they certainly generate a lot of interest.


Published 1/1/2008
S. Terry Canale, MD

Wait a minute—not so fast!

Due to these proliferating innovations, the AAOS fellowship began asking for help some time ago in assessing the efficacy and value of new technologies. The Board of Directors responded by establishing a Technology Assessment Project Team under the Council on Research, Quality Assessment, and Technology. The project team, chaired by Joshua J. Jacobs, MD, was charged with developing evidence-based methods to assess new orthopaedic technologies and, using these methods, develop recommendations for the use of new orthopaedic technologies.

The gender-specific knee
In December, the project team presented its first report—a technology overview on the gender-specific knee—to the AAOS Board of Directors. As a technology overview, the report summarizes published information. A technology assessment, on the other hand, would attempt to reach some conclusions about the effectiveness of a technology.

The technology overview was prepared using systematic review methodology. The project team reviewed only the articles relevant to the topic that fit their criteria as to Level of Evidence. Their findings are summarized in this issue of AAOS Now on page 43.

In general, the technology overview noted that differences in the femur exist between men and women, primarily in size and height. Men generally have larger femurs, are generally taller, and have a slightly smaller Q-angle than women. The evidence does not clearly suggest, however, that failure rates in women who have a traditional knee replacement are higher than in men. Finally, no pertinent literature is available to determine whether or not using a gender-specific knee replacement increases the success rate of total knee replacement in women.

The technology overview is not an official position of the AAOS, but an educational tool. It does not make recommendations for or against the use of gender-specific knee replacement components. It may not be what some fellows want to see—they may be looking for a definite position, pro or con—but based on the materials currently available, this overview is the most that can be said.

The entire technology overview report will be published in the February 2008 issue of the Journal of the AAOS; if you can’t wait until then, you can find it in the research section of the AAOS Web site at

Does controversy spur research?
Total knee replacement, as we all know, is an excellent operation that can make new knees out of old ones for both men and women. The controversy over the gender-specific knee might not be all bad, particularly if it results in refinements to the procedure that makes outcomes even better.

Through research, the truth will always come out; with a controversial topic, the truth just comes out quicker. Before you know it, significant clinical results will appear in peer-reviewed articles and it won’t be long before we have the truth, without having to rush to judgment. As a matter of fact, you’ll find both posters and podium presentations on the gender-specific knee at the 2008 AAOS Annual Meeting.

If you want to weigh in on this or any other topic, send us your comments. We will publish them in “Setting Now Straight.” Send your comments to AAOS Now, Attn: Setting Now Straight, 6300 N. River Rd., Rosemont, IL 60018, or e-mail them to