- Supine or seated
- Knee flexed to 20-30°
- Grab behind the proximal tibia and pull anteriorly (perpendicular to the tibia).
- Stabilize the femur with one hand (so it doesn’t track forward).
- Perform the same steps on the opposite (unaffected) knee.
Positive Sign / Significance
- Increased anterior translation compared to the other side (or a mushy, soft end-feel) = Anterior cruciate ligament injury
- When the knee is flexed to 90°, the hamstring tendons and iliotibial band also prevent anterior translation of the tibia in relation to the femur. Therefore, this Lachman’s test is preferred over the anterior drawer test.