Indications

The Lachman’s test is an orthopaedic test used to diagnose injury to the anterior cruciate ligaments (ACL) and posterior cruciate ligaments (PCL).

Procedure

Patient supine with knee bent 15°-30°.

  1. Lachmans Anterior: examiner stabilizes the patient’s femur with one hand and then pulls the tibia anteriorly with the other hand
  2. Lachman's Test for Anterior Cruciate Ligament (ACL)

    Lachmans Anterior: examiner stabilizes patient’s femur with one hand and then pulls the tibia anteriorly with the other hand

  3. Lachman’s Posterior: same procedure except repeated with the examiner pushing the tibia posteriorly
  4. Lachman's Knee Test  for posterior cruciate ligaments (PCL)

    Lachlan’s Posterior: Examiner pushing the tibia posteriorly

Interpretation

Anterior translation of more than 2mm of the tibia suggests a ruptured ACL (Often with a soft end fell).

Positive Lachman’s Test

Pain with normal anterior translation: ACL sprain.

Pain with increased anterior translation: ACL rupture.

Pain with normal posterior: PCL sprain.

Pain with increased posterior: PCL rupture

Clinical notes

This procedure is considered the gold standard for the evaluation of anterior cruciate and posterior cruciate knee ligament damage.