Ligament injuries are common and can occur at any joint. The knee and ankle are particularly vulnerable but it is sport specific. Ligaments are sprained when the joint is stressed beyond its normal range. Common causes of a ligament injury include: twisting, or landing awkwardly. It is most common when the ligaments around a particular joint are at full-stretch can cause it to tear away from the bone. The most common torn ligaments are knee ligaments and ankle ligaments. This is because the joints are weight-bearing and under high stress with change of direction sports or full contact sports.
Symptoms -
Sudden onset of pain and severe swelling.
Joint instability.
Impaired function eg can't walk or run.

Treatment -
Early Injury Treatment
Avoid the HARM Factors
Closed Kinetic Chain Exercises
Balance Enhancement Exercises
Medications
Soft Tissue Massage
Walking Boot
Electrotherapy & Local Modalities
Heat Packs
Joint Mobilisation Techniques