Which tests are used to assess an ACL tear?

Which tests are used to assess an ACL tear?

• A. Anterior Drawer & Lachman’s Test
• B. Posterior Drawer & Lachman’s Test
• C. McMurray & Thessaly
• D. Pivot Shift & Varus Stress

Answer: (A)

Testing an ACL tear focuses on how well the knee restrains forward (anterior) movement of the tibia relative to the femur. The two classic tests for this are the Anterior Drawer test and Lachman’s test because they directly provoke and measure that anterior translation. Lachman’s test is performed with the knee slightly bent (about 20–30 degrees). This position places the ACL under tension and makes even small tears easy to detect. It’s often the most sensitive bedside test for an ACL rupture because it reduces muscle guarding and swelling’s masking effect, giving a clearer sense of laxity. The Anterior Drawer test is done with the knee flexed to about 90 degrees and the tibia pulled forward. It also assesses how much the tibia can move anteriorly, but its accuracy can be influenced by patient relaxation and hamstring activity. Despite that, it remains a valuable, straightforward check for ACL integrity. The other tests focus on different structures: Posterior Drawer targets the PCL; McMurray and Thessaly assess meniscal tears; Pivot Shift and Varus Stress test evaluate rotational stability and collateral structures, which are not the primary tests for confirming an ACL tear. While Pivot Shift can indicate ACL issues, the combination of Anterior Drawer and Lachman’s tests most directly and reliably confirms ACL integrity in standard clinical assessment.

Testing an ACL tear focuses on how well the knee restrains forward (anterior) movement of the tibia relative to the femur. The two classic tests for this are the Anterior Drawer test and Lachman’s test because they directly provoke and measure that anterior translation.

Lachman’s test is performed with the knee slightly bent (about 20–30 degrees). This position places the ACL under tension and makes even small tears easy to detect. It’s often the most sensitive bedside test for an ACL rupture because it reduces muscle guarding and swelling’s masking effect, giving a clearer sense of laxity.

The Anterior Drawer test is done with the knee flexed to about 90 degrees and the tibia pulled forward. It also assesses how much the tibia can move anteriorly, but its accuracy can be influenced by patient relaxation and hamstring activity. Despite that, it remains a valuable, straightforward check for ACL integrity.

The other tests focus on different structures: Posterior Drawer targets the PCL; McMurray and Thessaly assess meniscal tears; Pivot Shift and Varus Stress test evaluate rotational stability and collateral structures, which are not the primary tests for confirming an ACL tear. While Pivot Shift can indicate ACL issues, the combination of Anterior Drawer and Lachman’s tests most directly and reliably confirms ACL integrity in standard clinical assessment.