ACL or Anterior Cruciate Ligament is one of the most important ligaments in the knee. It helps control the stability of our knee during movements in two planes – antero-posterior (front-to-back) and rotatory (pivoting). This stability not only makes the knee comfortable but also protects other vital structures in the knee. The ACL ligament has two bundles (anteromedial and posterolateral) and an inherent blood supply. The ACL can be torn through a variety of mechanisms and due to various factors which are both internal (specific to the patient) and external (not specific to the patient).