Knee

Medial collateral ligament injury

Mechanism

A valgus force on the knee, usually from an outside blow or landing with the knee falling inward. The ligament is fused to the medial meniscus, which explains why both are often damaged together.

Recognition

Tenderness along the course of the ligament, from the medial epicondyle to the medial tibia, and pain or gapping on the valgus stress test at 20 to 30 degrees of flexion.

Course

Of the knee ligaments this one heals best without surgery: it lies outside the joint and has a good blood supply. Gapping in full extension means more than the MCL alone is damaged.

Structures

• Medial collateral ligament of the knee (MCL / Tibial collateral ligament)
• Medial meniscus of the knee (Body, anterior horn, posterior horn)

Joints involved

• Knee joint

Clinical tests

• Valgus and varus stress test

Sources

• Magee DJ, Manske RC. Orthopedic Physical Assessment, 7e editie. Elsevier. 2021