Relationship between ratio of medial to lateral quadriceps thickness and the knee joint angle during single-leg landing

This study investigated the relationship between ratio of vastus medialis (VM) to vastus lateralis (VL) muscle thickness and the knee valgus angle at initial contact during single-leg landing. Ultrasound images of VM and VL were obtained from thirteen healthy subjects. All subjects performed single-leg landing from a 30-cm-height platform and the knee valgus angle was measured at initial contact. Negative correlation was found between VM:VL ratio of muscle thickness and the valgus angle. Individuals who have less VM:VL ratio of muscle thickness could experience higher risk of anterior cruciate ligament injuries.