An injury to the anterior cruciate ligament (ACL) may be described as a partial tear, complete tear or an avulsion (tearing away) from the bone attachments that form the knee.
Review Date 7/8/2020
Updated by: C. Benjamin Ma, MD, Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery, San Francisco, CA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.