The medial collateral ligament is one of the most important ligaments for the stability of the knee, since it strengthens the medial side of the knee, intercepting the forces that tend to cause deformity in valgus. If the forces that displace the leg outwards exceed the force that the medial collateral ligament can resist, then its rupture occurs.
The most common mechanism for tearing the medial collateral ligament is direct boring from the outside of the knee. The medial collateral ligament tear is usually accompanied by other injuries, with the most common being those of the anterior cruciate ligament and the medial meniscus. The coexistence of injuries in all 3 of these structures is called the “unfortunate triad”, and is an injury that is often encountered in athletes.
Rupture of the medial collateral ligament is mainly accompanied by pain on the medial surface of the knee. However, depending on the degree of the rupture and the coexisting injuries, there may be:
- hemarthrosis (collection of blood in the knee joint)
- knee involvement (inability to fully extend or bend the knee), if there is a meniscal tear or osteochondral damage.
- possible feeling of insecurity or even episodes of knee instability.
The diagnosis of ligament rupture is clinical and is based on the mechanism of injury and the clinical examination. Magnetic resonance imaging can confirm the diagnosis and highlight possible accompanying lesions, which affect the patient’s treatment plan.
Treatment is usually either conservative, and depends on the extent of the tear and whether there are accompanying ligamentous or other coexisting injuries.
A partial tear of the medial collateral ligament can heal and is therefore treated conservatively, with rehabilitation including strengthening and proprioceptive exercises. In cases of total rupture of the medial collateral ligament, conservative treatment can again be applied, with the recovery time this time being a little longer.
