Pain in old fractures may be related to delayed fracture healing, fracture non-union, and abnormal fracture healing, such as insecure fracture repositioning, infection, and premature removal of fixation. 1. Delayed fracture healing: the main cause of which is poor fracture repositioning and fixation, followed by malnutrition of the body, which leads to abnormal movement of the fracture end and causes pain. 2. Non-union of fracture: research shows that the causes of non-union of fracture may include infection, serious injury, improper treatment, bone defect, fracture breaks with more soft tissues and so on. 3. Malunion of fracture: It may be due to poor repositioning of the fracture or premature removal of the fixation, which leads to improper muscle pulling, so pain will occur. To summarize, there are many causes of old fracture pain, and patients with old fracture pain are recommended to have a timely follow-up. Usually, after the occurrence of fracture, you need to go to the hospital, strengthen the management of daily life, and cooperate with the doctor to carry out standardized treatment, so as to avoid delaying the condition.