2006-5-23
I'm Bob Doughty with the VOA Special English HEALTH REPORT.
Women who have problems with artificial knee implants may get some help soon. The United States Food and Drug Administration recently approved a replacement knee designed especially for women.
About four hundred thousand people in the United States have knee replacement operations each year. More than sixty percent of them are women.
People who have damaged cartilage in their knees are good candidates for a replacement operation. Cartilage is a kind of soft connective tissue. Injuries or disease may cause cartilage loss. When cartilage is gone in the knee, bones rubbing together may restrict movement and cause severe pain.
In a replacement operation, doctors remove damaged parts of the thighbone, the shinbone and the kneecap. They replace the damaged parts with parts made of metal and plastic.
Studies have shown that a knee implant lasts about fifteen years. Women report more problems with implants than men do. Problems include pain and difficulty moving the knee. In some cases, another operation is needed. Experts believe this is because makers of knee implants are more concerned about size than shape. A man's knee is shaped differently than a woman's. Men usually have shorter and wider knees. Women's knees are smaller and narrower.
Makers of the new knee implant say it is shaped to fit a woman's bone structure. They say women should experience less pain and recover more quickly. Currently, complete recovery can last three months or longer. Makers of the new product say it will also make knee replacement operations easier to carry out.
Zimmer Holdings Incorporated built the new Gender Solutions knee. The company already makes other replacement knees and hips.
Nine medical experts helped to design the Gender Solutions knee. One of them is Kim Bertin of L.D.S. Hospital in Utah. He compared existing knee implants to putting men's shoes on women's feet.
Other experts question the effectiveness of the new knee. They believe it is just a marketing tool to interest women. No studies have shown that the new implant works better than other products.
Also, Zimmer has competition. Another company, Stryker Orthopedics, says it makes a knee to fit both men and women.
This VOA Special English HEALTH REPORT was written by Cynthia Kirk. I'm Bob Doughty.