What is assessed with the Abduction (Valgus) stress test?

The Abduction (Valgus) stress test is specifically designed to assess the integrity of the Medial Collateral Ligament (MCL). During the test, a force is applied to the lateral aspect of the knee while the ankle is stabilized, creating a valgus stress. If the MCL is intact, the knee remains stable under this force; however, if there is damage or a tear to the MCL, the knee will exhibit increased laxity or gapping on the medial side when stress is applied. This test is fundamental in evaluating injuries sustained in sports or trauma where the knee may be subjected to excessive stretching forces.

In contrast, the assessment of the Lateral Collateral Ligament (LCL), meniscal tears, or the Anterior Cruciate Ligament (ACL) injuries involves different tests and mechanisms of evaluation, making them unsuitable for the purpose of the Abduction (Valgus) stress test. Each of these ligamentous and meniscal injuries has specific tests that target their individual anatomy and function, highlighting the focused role of the Abduction stress test in MCL assessment.