April 2, 2007



LEWISBURG, Tenn. – In 2006, new technology known as the gender-specific knee implant was introduced and one of the first three procedures in Tennessee was conducted at Maury Regional Hospital by H. James Wiesman, Jr., M.D.  On Thursday, April 12, Dr. Wiesman will present a free seminar on this new technology in knee replacement for women. The program will begin at 6:00 p.m. in the conference room at Marshall Medical Center.

The gender-specific knee implant was designed based on three distinct shape differences between the knees of women and men:

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. This new implant is proportionally contoured to the entire bone to provide a more precise fit.

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. This new implant is thinner in shape in the front so the knee replacement more appropriately matches the natural female anatomy.

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. This new implant was designed to accommodate the different tracking angle and function more like a woman’s natural knee.


According to the National Center for Health Statistics, nearly two-thirds of the 400,000 knee replacements conducted annually are performed on women. The implant’s goals include alleviating knee pain and restoring mobility, while offering fit and function that is optimized for the characteristics more commonly seen in female patients.



© 2008 Maury Regional Medical Center