The anterior cruciate ligament (ACL) connects the upper and lower leg bones and helps stabilize the knee. It gets the most use in athletes who play a sport such as basketball that involves quick cuts and changes in direction.

Those athletes are also the most likely to suffer a torn ACL -- the same injury that took down Chicago Bulls player Derrick Rose in the first round of the National Basketball Association playoffs last weekend.

The new findings support past research suggesting that when those injuries occur, it's better to use a person's own tissue to repair their ACL -- also known as an autograft, said Dr. Cassandra Lee, a sports medicine doctor at the University of California, Davis, who wasn't involved in the new study.

Typically, the tissue for an autograft is taken from a person's hamstring or patellar tendon. The alternative -- an allograft -- is donated tissue from a cadaver.

For the new study, researchers at the United States Military Academy in West Point, New York tracked members of their 2007 through 2013 classes who had ACL reconstruction before entering the Academy. The students ranged from 18 to 23 years old.

Dr. Brett Owens, the study's senior investigator and chief of orthopedic surgery service at Keller Army Hospital in West Point, told Reuters Health the researchers started their study after noticing an increase in the number of reconstructions using donated tissue that had failed.

They identified 120 cadets who'd had a total of 122 ACL reconstructions. Of those, 106 had their ACLs reconstructed with autografts; the rest had donor tissue.

Since all cadets receive medical care at the Academy, the researchers knew 20 of the ACL reconstructions failed -- meaning cadets had to have the surgery re-done. Those failures happened an average of a year and a half after students started at the Academy.

Of the reconstructions that failed, 13 were from surgeries using the cadets' own tissue -- about 12 percent of all autografts -- and seven were from cadavers, accounting for 44 percent of reconstructions that used donated tissue.

The researchers reported that cadets who had ACL allograft reconstruction were almost seven times as likely to need a second surgery compared to when cadets' own tissue had been used.

Owens and his colleagues also reported that ACL allograft reconstructions failed much earlier, on average, than autografts.

They wrote in the American Journal of Sports Medicine that they recommend the use of autografts in young athletes.

There are about 150,000 ACL injuries every year in the U.S., according to the American Orthopaedic Society for Sports Medicine. The cost of reconstruction surgery varies, but typically runs between $5,000 and $7,000.

DIFFERENT APPROACHES

Lee told Reuters Health the new study is "neat," because the cadets were in a very controlled environment. All of them must meet certain physical requirements to enter the Academy, and once there they engage in similar activity levels.

According to the researchers, every cadet must take part in either intramural, club or intercollegiate sports for all but two semesters of their four years.

For others with an ACL injury, there may be different options besides ligament reconstruction, according to Dr. C. Benjamin Ma, chief of sports medicine and shoulder service at the University of California, San Francisco.

Ma, who was not involved with the new study, told Reuters Health that treatment depends not just on patients' age and activity level, but also on their preferred sport. People not involved in cutting sports like soccer or basketball may choose not to have reconstruction, he said.

For them, possible treatments include muscle retraining, hamstring conditioning, core stability exercises, activity modification and possibly the use of a brace.

Lee said it's also important to have a thorough recovery.

"We're very good about getting people back to play right now, but their knee has actually gone through significant trauma," said Ma. "This is kind of a long-term issue."

SOURCE: bit.ly/IlkMQH American Journal of Sport Medicine, online April 24, 2012.

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