The lateral collateral ligament is injured as part of the lateral ligament complex and rarely in isolation. It prevents postero lateral translation and medial rotation of the tibia. Anatomy- It extends from the head of the fibula to the lateral femoral epicondyle. It is a round band. The tendon of the biceps is closely related to it.

Symptoms
-History of injury
-Pain on the lateral aspect of the knee.
-Inward thrust of the leg on walking.
-Opening up of the lateral aspect of the knee on a varus strain.

Signs and investigations
Investigations- Stress X rays are useful. An examination under anaesthesia is the most useful investigation. An MRI scan confirms the disruption of the ligament.

Treatment
In isolated cases the ligament can be repaired. In complex lateral complex injuries reconstruction is done with hamstring tendons (semitendinosus) Postoperative bracing is necessary