About a quarter of recreational skiers who tear their anterior cruciate ligament (ACL) on the slopes can be successfully treated without surgery, according researchers at Hospital for Special Surgery in New York City. Their article appears online ahead of print in the journal Knee Surgery, Sports Traumatology, Arthroscopy.

The study found that at 6 to 12 weeks post-ACL tear, results from 2 tests that involve only the physical manipulation of a knee can identify skiers with a torn ACL who will recover without surgery.

The researchers examined records of patients treated between 2003 and 2008 to identify recreational alpine skiers who were seen within 6 weeks of a first-time ACL tear. To be included, skiers had to have ACL rupture documented on an MRI after the injury and a minimum of 2 years follow-up. Patients were excluded if they had injured ligaments in both knees. They identified 63 acute, first-time skiing ACL tears; 29 of these patients did not undergo an ACL operation.

The researchers then separated the 29 patients into 2 groups, those that had low-grade Lachman scores and negative pivot shift tests, indicating a potentially healed ACL, and those that had Lachman scores of 2+ and a positive pivot shift test indicating a damaged ACL.

Six to 12 weeks after injury, 17 of the 29 skiers who did not have surgery had a Lachman score of 0 to 1 and a negative pivot shift test. Six of these patients were lost to follow-up, but 11 returned for a study-specific follow-up evaluation at more than 2 years post-injury. These patients completed questionnaires that gauged how well the knee was functioning and how their ski accident had occurred. They also underwent Lachman and pivot shift tests and a KT-1000 test to measure motions of the shin bone relative to the thigh bone.

Skiers described injuring their ACL in tumbles where the ski had rotated too far. Physical exams revealed that 10 of the 11 patients still had Lachman scores of 0-1 and negative pivot shifts tests, and only 1 patient's scores had deteriorated to a Lachman Grade 2+. None of the patients, however, complained about knee instability. Eight had returned to skiing without the use of a brace; 3 no longer skied. KT-1000 test results also were positive.

APTA member Greg Fives, PT, coauthored the article.