Partial Anterior Cruciate Ligament Injury

Anterior cruciate ligament (ACL) tears are one of the most common knee injuries, with over 200,000 injuries occurring in the United States each year. Athletes are the most at-risk group for complete ACL ruptures, which are diagnosed on clinical exam and imaging. However, there is no standardized definition of what constitutes a partial ACL tear. Partial ACL tears most commonly occur as a noncontact injury during rapid deceleration or abnormal rotation and pivoting. A thorough clinical exam and imaging are needed to determine the extent of the tear. Techniques that assess injury extent include the pivot shift, Lachman’s test, lever, arthrometer, and MRI. The gold standard for diagnosis is arthroscopy. The decision to treat through conservative or surgical means is based on functionality and stability observed during diagnostic tests, as well as risk for progression to complete rupture. Conservative treatment involves immobilization and subsequent rehabilitation with a return to sport at 6–12 weeks. Operative management includes reconstruction or selective bundle repair and have overall positive outcomes. Physical rehabilitation should be done following surgery with an expected return to sport after 6–9 months dependent upon the type of surgical management undergone. Patients treated with surgery have overall better outcomes than conservative treatment and should be considered among patients with high activity expectations.