Courtesy: Prof NabileEbraheim, University of Toledo, Ohio, USA
LACHMAN’S TEST
(ACL) INJURY
- Lachman’s test is the most sensitive examination test for ACL injury
- The anterior cruciate ligament is located in front of the knee.
- The ACL keeps the tibia from sliding out in front of the femur and provides rotational stability to the knee.
- Rupture of the anterior cruciate ligament is a condition commonly seen in sports due to a non-contact pivoting injury.
Patient evaluation
• Patient will feel a “POP” within the knee
• Pain
• Immediate swelling
• There is usually hemorrhaging within the knee joint
• Knee giving way
- If aspiration of the knee shows hemarthrosis, then there is a 75% chance of an ACL tear and meniscal injury
How do you perform the Lachman’s test?
- The patient should be lying supine and completely relaxed.
- Make sure that the patient’s hip muscles, quadriceps, and hamstring muscles are all relaxed
- Bend the knee to about 20-30 degrees
- Stabilize the femur with one hand and with the other hand, pull the tibia anteriorly and posteriorly against the femur.
- With an intact ACL, as the tibia is pulled forward, the examiner should feel an end point.
- The examiner should feel a firm end point.
- With a rupture, the ACL will be lax and the examination will feel softer with no end point.
- The tibia can be pulled forward more than normal (anterior translation).
- Lachman’s test is the best examination to diagnose a tear of the ACL.
- Be aware that a PCL tear may give posterior subluxation of the tibia and a false positive Lachman’s test.
Radiological examination
- MRI of the knee joint shows bone lesions or bruising associated with tears of the ACL.
- These injuries typically located at the middle of the femoral condyle and posterior part of the tibia laterally.
Khoi Tranchi says
Very very good clip
Vivasvan says
Thank you .very clear