Reverse Lachman Test: How to Check for PCL Tears

The Reverse Lachman Test is a specific orthopedic maneuver used to evaluate the Posterior Cruciate Ligament (PCL). It is performed similarly to the standard Lachman test but stresses the knee in the opposite direction.

1. Purpose

The primary purpose of the Reverse Lachman Test is to **test for** the integrity of the Posterior Cruciate Ligament (PCL). It is a modification of the standard Lachman test, but instead of pulling the tibia forward, the examiner pushes it backward.

2. How to Perform

1. The patient is positioned in supine (lying on their back). Alternatively, this can be done prone.
2. The examiner flexes the patient's knee to 20-30 degrees.
3. The examiner stabilizes the distal femur (thigh) with one hand.
4. The examiner grasps the proximal tibia (shin) with the other hand.
5. The examiner applies a firm posterior (backward) force to the tibia, attempting to push it backwards.

3. Positive & Negative Sign

Positive Sign (Test is POSITIVE):
A positive test (indicating a PCL tear) is:

• Excessive posterior translation (movement backward) of the tibia relative to the femur compared to the uninjured side.
• A "soft" or "mushy" end-feel (lack of a solid stop).

Negative Sign (Test is NEGATIVE):
A negative test is a firm, distinct end-point (hard stop) with minimal posterior movement.