THURSDAY, March 6 (HealthDay News) -- Baby Boomers are staying active on the basketball court and soccer field, and now new research suggests their injured knees can tolerate surgery just as easily as their younger counterparts.

A new, but small, study found that men and women in their 50s and 60s did well after undergoing reconstruction of injured tissues in their knees known as anterior cruciate ligaments.

A couple decades ago, surgeons wouldn't have bothered to fix these injuries in people over 50, or even 40. Now, "you're never too old to have your ACL reconstructed," said Dr. Diane Dahm, an assistant professor of orthopedic surgery at the Mayo Clinic in Rochester, Minn.

She presented the research Wednesday at the American Academy of Orthopaedic Surgeons' annual meeting, in San Francisco.

The ACL is a kind of anchor that holds the knee together and can become injured when someone is playing sports and tries to turn and pivot, said Dr. Robert Gotlin, director of orthopedic and sports rehabilitation at Beth Israel Medical Center in New York City. Athletes who play sports like football, lacrosse, basketball and soccer are especially prone to the injury, he noted.

Tearing and extreme stretching hurt the ACL. According to Dahm, an injury could come while landing after a rebound on the basketball court. Injuries are also possible off the field, perhaps while changing direction quickly while getting out of a car. Still, she said, most of the injuries are related to sports.

In decades past, surgeons were reluctant to perform procedures on people who had injuries after the age of 40, because it was assumed that "your athletic life is done," Gotlin said. "You don't fix the ACL, because you don't really need it."

Times, and attitudes, have changed.

"Boomers are active, and they're tearing [their ACLs] for the right reasons, because they're working out," he noted. "They're getting hurt, because they're doing more."

As a result, older patients are going under the knife so they can stay active. Gotlin said he's performed surgeries on patients in their 80s who returned to the ski slopes, although rehabilitation can take months.

In the new study, researchers looked at the records of 34 patients who underwent ACL reconstruction surgery between 1990 and 2002 at the Mayo Clinic. All were between the ages of 50 and 66.

The surgery reconstructs the ACL with other tissue, sometimes from the patient's own body.

Eighty-three percent of the patients were considered to have returned to a normal or near-normal state after the surgery, and 83 percent returned to playing sports. However, five of the 34 patients required more knee surgery.

"Some people have felt that it's possible that reconstructing the ACL in these older patients might lead to an increased risk of complications like stiffness in the knee, but our complication rate was very low," Dahm said.

The message, she said, is that the surgery works: "They were able to return to a fairly high level of activity."

More information

Learn more about ACL injuries from the National Institutes of Health.