Valgus Stress Test for Medial Collateral Ligament (MCL) Injuries Medial collateral ligament injuries are among the most prevalent knee injuries seen in primary care. It’s therefore of particular interest for our healthcare systems that physicians and physiotherapists are able to filter patients with suspected MCL injury prior to referring them to secondary care. The Valgus or Abduction Stress Test is designed to stress the medial collateral ligament. In the 0° position, the test stresses the Pos