There is no quick recovery from a lateral dorsal foot sprain. The bulge of lateral dorsal sprain may be caused by localized soft tissue edema and rupture of lateral collateral ligament, and common treatments include physical therapy, medication and surgery. 1. Local soft tissue edema: caused by trauma to the lateral side of the ankle joint caused by local soft tissue edema, sprain within 72 hours to avoid further aggravation of the local use of physical cold compresses, elevation and immobilization of the affected limb to avoid stress, and the use of non-steroidal anti-inflammatory pain medication under the guidance of a physician, such as sodium aceclofenac or ibuprofen, and so on. 2. Lateral collateral ligament rupture: If the injury causes the lateral collateral ligament to rupture, the broken end retracts and forms a bulge, which is the broken end of the ligament, and it is necessary to carry out magnetic examination of the ankle joint to make a clear diagnosis, and if it is clear that the ligament is ruptured, it is necessary to carry out ankle surgery to repair the damaged ligament. If the pain after the sprain is severe and lasts for a long time, it is recommended that patients with lateral instep sprains and bulges go to the hospital as soon as possible and follow the doctor’s instructions for standardized treatment.