The most common reasons why ankle sprains have been bad include premature activity, serious injury, hidden bone fracture, secondary injury, etc. It is recommended to go to the hospital for examination in time. 1. Premature activity: If you don’t follow the doctor’s instruction to go down to the ground too soon after the ankle sprain, it may aggravate the injury and is not conducive to the recovery of the condition. 2. Serious injury: if the patient after ankle sprain injury is more serious, or even a ligament rupture, and did not receive formal treatment, sprain has not been easy to get well. 3. Hidden bone fracture: ankle sprain may also be accompanied by a fracture, the fracture may be less obvious to be missed, may also lead to the sprain continues not to heal, need to be timely X-ray examination. 4. Secondary injury: In the process of recovering from a sprained ankle, inadvertently causing a secondary injury can also lead to delayed recovery from a sprained ankle. If the ankle sprain continues to fail to recover, it is recommended to go to the hospital in time to find out the situation, the doctor targeted treatment.