The Gender Solutions™ High-Flex Knee, touted as the first knee replacement specifically designed for women’s anatomy, was approved yesterday by the FDA. The agency has issued 510(k) clearance for the system. Developed by Warsaw, Indiana-based Zimmer Holdings, Inc., the device accommodates the following female anatomy requirements:
1. Narrower Shape, Proportioned to Female Anatomy: When determining the appropriate-sized implant, surgeons measure the end of the femur from front to back and from side to side. Women’s knees typically are narrower from side to side, and are more trapezoid-shaped, whereas men’s knees are more rectangle-shaped. Surgeons typically choose the implant size based on the front-to-back measurement, which is key in allowing the knee to move and flex properly. However, an implant that fits a woman’s knee from front to back often will be too wide from side to side, leading to the implant overhanging the bone and potentially pressing on, or damaging, surrounding ligaments and tendons, possibly causing pain. The Gender Solutions High-Flex Knee is proportionally contoured to the entire bone to provide a more precise fit.
2. Thinner Shape: The bone in the front of a woman’s knee is typically less prominent than in a man’s knee. Therefore, when a traditional implant is used to replace the damaged bone, the joint may end up feeling and functioning better than before surgery but still feel “bulky,” which may result in pain and decrease optimal function. The Gender Solutions Implant is thinner in shape in the front so the knee replacement more appropriately matches the natural female anatomy.
3. More Natural Tracking: The angle between the pelvis and the knee affects how the kneecap tracks over the end of the femur as the knee moves through a range of motion. Women tend to have a different angle than men due to their specific shape and contour. Historically, implants have been designed based on an average between the size of women’s and men’s knees, and therefore, the traditional artificial knee may tend to track at an angle that leads to a woman’s knee feeling “unnatural” as it moves. “It’s like driving with two tires on the shoulder of the road – you can do it, but it doesn’t feel quite right,” Dr. Booth [Robert E. Booth, M.D., Chief of Orthopaedic Surgery at Pennsylvania Hospital ed.], said. The Gender Solutions Knee Implant was designed to accommodate the different tracking angle and function more like a woman’s natural knee.
When placing traditional implants, some surgeons accommodate women’s differences by removing more bone or repositioning the implant during surgery, but their ability to make the implant precisely conform to the patient is limited. The Gender Solutions High-Flex Implant was designed so the surgeon can more closely match the female patient’s knee anatomy.
Not to repeat ourselves, but we believe that the device is probably strong enough for a man, but pH balanced for a woman. And, hopefully, it comes in a pastel color palette.
The press release…
Zimmer Unicompartmental High Flex Knee System website…
Zimmer’s website for patients…
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