The annual incidence of acute knee injury in the United States is estimated to be 300 cases per 100,000 population.
Collateral ligament injuries account for 25% of patients presenting to emergency rooms with acute knee injury. Peak incidence of collateral ligament injuries occurs in adults aged 20-34 years. The National Collegiate Athletic Association (NCAA) injury surveillance system reported 2.1 medial or lateral collateral injuries per 1000 player exposures in games across all NCAA sports over 1 year.[5] Even noncontact sports, such as gymnastics and swimming, can lead to collateral ligament injuries