The function of the collateral ligaments of the knee is to stabilise the knee from varus / valgus forces. Consists of a Medial & Lateral ligament.
Mechanism of injury :
1. Medial Collateral [ MCL]
Excessive Valgus forces to partially flexed knee. Direction of force lateral to medial. Can be contact or non-contact.
2. Lateral Collateral Ligament [LCL]:
Usually a severe, high energy, direct Varus forces. Direction of force, medial to lateral. Less common than MCL strains.
- Avulsion of biceps femoris tendon.
- Posteriolateral corner tenderness > ACL tear
- Grade III tear associated with PCL rupture > high instability >surgery