The medial collateral ligament (MCL) and the lateral collateral ligament complex (LCL) provide support along the inner and outer sides of the knee and keep the tibia from bending inward (medially) or outward (laterally) relative to the femur.

Medial and Lateral Knee Ligament Injuries

Classification of collateral ligament injuries:

  • Grade I: Low grade injury (sprain) with stretching or microtearing of the ligament fibers.
  • Grade II: Intermediate grade injury with macroscopic partial tearing and stretching of ligament fibers. Some intact fibers maintain function.
  • Grade III: Completely torn/ruptured ligament with lost function.


A. Grade I or Grade II Injuries:

  • R.I.C.E. (rest, ice, compression, and elevation) in the acute phase of injury.
  • Anti-inflammatory drugs (NSAIDs) to help with pain.
  • Knee brace to allow healing.

B. Grade III Injury

  • R.I.C.E.
  • NSAIDs
  • Physical therapy exercises
  • Even grade III MCL tears may heal. In certain circumstances, your surgeon may recommend surgical repair to restore function.

Healing of collateral ligament sprains typically takes from four to six weeks, depending on the severity of injury.