Artificial Knee Ligament Wins Approval
The Food and Drug Administration announced approval Thursday of the first artificial ligament--a braided strand of synthetic fiber used to repair certain types of sports injuries--designed to enable an athlete to walk or run in a matter of weeks rather than six or eight months.
The artificial ligament attaches between the thigh and the lower leg bone to stabilize the knee after the natural ligament--called the anterior cruciate--is torn, a frequent occurrence in football, soccer and skiing.
The artificial ligament is made of expanded polytetrafluoroethylene, or Gore-Tex, a tough, durable material already used in sutures and blood vessel grafts, as well as in ski parkas, running clothes and foul-weather gear.
It has been used experimentally for two years on more than 1,000 patients at 27 hospitals in the United States.
The FDA said that many patients implanted with the device can walk and run within several weeks, compared to the six to eight months required after traditional surgery, in which a patient’s tendon is grafted in place of the ligament. This procedure generally requires a long recovery period to enable the graft to grow strong and become firmly attached, the agency said.
“These disabilities are particularly tragic because many of the torn ligaments occur in young, vigorous people,” said Dr. Frank Young, the FDA commissioner. “With the artificial ligament, surgeons may be able to get many of these people back on their feet--literally--in weeks instead of months.”
An eyelet at each end of the braid permits it to be screwed into the bone, with one end going into the back of the femur, or thigh bone. The other end runs through the top of the tibia, or major leg bone, to the front of that bone, where it is fixed with a screw. Bone growth eventually holds the ligament, and the screws become unnecessary.
The agency said that the ligament has been approved only for patients in whom tendon grafting has failed, but added that this limitation could be eliminated as more of the devices are implanted. The ligament is manufactured by W. L. Gore and Associates of Flagstaff, Ariz.
