Which condition is indicated by a positive anterior "drawer sign"?

A positive anterior "drawer sign" indicates that the tibia can be moved forward significantly when pulled, demonstrating excessive anterior translation relative to the femur. This finding is characteristic of an injury to the anterior cruciate ligament (ACL), which is crucial for stabilizing the knee joint and preventing forward displacement of the tibia.

In the case of an ACL injury, the integrity of the ligament is compromised, leading to this increased mobility. Clinicians often use this test during the examination of a knee injury to assess for possible ACL damage. The sign is specifically named for the action of pulling the tibia forward (anterior) from the knee joint.

Other knee conditions might involve different signs or physical examination findings. For instance, a meniscus tear is typically associated with joint locking, pain, or swelling but does not specifically result in a positive anterior "drawer sign." Similarly, while a posterior cruciate ligament (PCL) injury would result in a positive posterior drawer sign, it would not be indicated by the anterior drawer test. Patellar tendonitis primarily involves pain and tenderness at the patellar tendon, with no relationship to the drawer test findings. Thus, the positive anterior "drawer sign" is definitive for an ACL injury.