Injuries to the lateral collateral ligament usually require a cast. Immobilization and braking in a cast for 3-4 weeks will help the lateral collateral ligament to recover. If the patient has a lateral collateral ligament injury, it is recommended that the patient be immobilized in a cast, which can effectively avoid weight-bearing activities of the joint, limit the flexion and extension of the joint area, reduce the re-strain of the injured ligament, and is also conducive to the repair of the lateral collateral ligament. If the patient is not immobilized with a plaster cast, it is easy to pull the injured lateral collateral ligament excessively when the joint is flexed or extended or when weight-bearing activities are carried out, which increases the swelling and pain in the ligament area, and affects the recovery of the lateral collateral ligament. If the patient has a lateral collateral ligament injury, it is generally recommended to be immobilized with a plaster cast so as to create favorable conditions for the recovery of the ligament.