Reviewed by Dr Subhajit Maji — Orthopaedic Surgeon (AIIMS)
Special Interest: Sports Injury, Knee Ligament Surgery & Arthroscopy
Key Points:
- Lachman test is the most sensitive clinical test for ACL injury.
- Used to assess anterior stability of the knee.
- Positive test suggests anterior cruciate ligament tear.
- Essential examination in sports knee injuries.
What is the Lachman Test?
The Lachman test is a clinical examination maneuver used by orthopaedic surgeons to evaluate the integrity of the anterior cruciate ligament (ACL). The ACL stabilizes the knee by preventing excessive forward movement of the tibia relative to the femur.
It is considered the gold standard clinical test for detecting ACL injuries due to its high sensitivity and reliability.
Why is the Lachman Test Performed?
- Sports injuries involving twisting mechanisms.
- Knee instability or giving way.
- Acute swelling after trauma.
- Evaluation before MRI confirmation.
How is the Lachman Test Performed?
The patient lies supine with the knee flexed approximately 20–30 degrees. The examiner stabilizes the femur and applies anterior force to the tibia to assess anterior translation and endpoint quality.
- Normal: Firm endpoint.
- ACL injury: Increased translation with soft endpoint.
Orthopaedic Pearl: Lachman test is more sensitive than anterior drawer test because hamstring guarding is minimized.
Accuracy of the Lachman Test
- High sensitivity for ACL tears.
- Best performed in acute injury phase.
- Combining with pivot shift increases diagnostic confidence.
For Medical Students & Exam Preparation
If you want deeper orthopaedic learning including clinical examination MCQs, memory tricks, and exam-focused explanations, explore:
OrthoMCQ.in — Orthopaedic MCQs with Concept-Based Learning
This resource helps bridge clinical examination skills with exam preparation for orthopaedic trainees.
When Should You Consult an Orthopaedic Surgeon?
- Knee instability after injury.
- Persistent swelling or pain.
- Difficulty returning to sports.
- Repeated giving-way episodes.
Written by: Dr Subhajit Maji, Orthopaedic Surgeon (AIIMS)
Last Updated: February 2026
This educational content is for informational purposes only and does not replace professional medical consultation.