What is an anterior drawer test of the knee?
The anterior drawer test of the knee is an important diagnostic tool used to assess the integrity of the anterior cruciate ligament (ACL). The ACL is one of the key ligaments that provide stability to the knee joint, preventing the tibia from sliding forward relative to the femur.
The purpose of the anterior drawer test is to test the ACL's current health, whether it is injured or not. Sudden stops, changes in direction, or direct impacts can result in an ACL tear, making it a particularly common injury among athletes. The test helps to determine whether the ligament is intact, partially torn, or completely ruptured.
How to do the anterior drawer test of the knee
These are the steps to perform the anterior drawer test for the knee:
- The patient lies supine on a flat surface with the hips flexed to 45 degrees, the knees bent to 90 degrees, and the feet flat on the table.
- The examiner sits on the toes of the tested leg to stabilize it.
- The examiner grasps the lower leg just below the tibial plateau or joint line.
- The examiner then attempts to move the lower leg forward, assessing the degree of anterior movement and end feel.
If the tibia moves forward significantly or if there's a lack of a firm end feel, the test is considered positive, suggesting potential damage to the ACL. A positive anterior drawer test indicates that the ACL is either partially or completely torn. A negative test indicates an uninjured knee.
However, this test should not be used in isolation for diagnosis. Additional assessments, such as the Lachman test or imaging like MRI, are often employed to confirm the extent of the injury.
When interpreting the results, it's important to consider the patient's overall clinical picture. A positive test might be associated with symptoms such as knee instability, pain, or a history of trauma. In some cases, patients with a positive test may have difficulty performing activities that involve pivoting or sudden directional changes.






