What is Lachman Test?
- Lachman Test is used to Assess the integrity of the anterior cruciate ligament (ACL)
How it's Performed?
- The patient is positioned supine with their injured knee flexed to 20 to 30 degrees while also slightly externally rotating the injured leg to relax the iliotibial band.
- The examiner then uses one hand to stabilize the distal femur while using the other hand to grasp the proximal tibia.
- Next, an anterior force is applied to the proximal tibia in an attempt to sublux the tibia forward while keeping the femur stabilized
What does a positive Lachman Test mean?
- The Lachman Test is considered positive if there is excessive anterior translation of the proximal tibia greater than the uninjured side and also a lack of a firm endpoint.
- Endpoints are graded from “hard” to “soft,” and have been nominally classified as :
- A (firm, hard endpoint)
- B (absent, soft endpoint).
Sensitivity & Specificity
- Sensitivity: 87 %
- Specificity: 93 %