Risk Factors and Predictors of Subsequent ACL Injury in Either Knee After ACL Reconstruction

Anterior cruciate ligament (ACL) reinjury results in worse outcomes and increases the risk of posttraumatic osteoarthritis. PURPOSE: To identify the risk factors for both ipsilateral and contralateral ACL tears after primary ACL reconstruction (ACLR). STUDY DESIGN: Cohort study; Level of evidence, 3.

Data from the Multicenter Orthopaedic Outcomes Network (MOON), a prospective longitudinal cohort, were used to identify risk factors for ACL retear. Subjects with primary ACLR, no history of contralateral knee surgery, and a minimum of 2-year follow-up data were included. Age, sex, Marx activity score, graft type, lateral meniscal tear, medial meniscal tear, sport played at index injury, and surgical facility were evaluated to determine their contribution to both ipsilateral retear and contralateral ACL tear.