The pain of sitting for a long time after falling on the tailbone of the buttocks may be caused by tailbone fracture, sacrococcygeal ligament injury or coccygeal osteitis. 1. Tailbone fracture: tailbone fracture can be caused after a fall, the main symptom is the pain and discomfort in the tailbone when sitting, the longer you sit, the more intense the pain, and even lying down, walking, you may feel the pain. 2. Sacrococcygeal ligament injury: A fall on the hip can lead to misalignment of the tailbone and sacral vertebrae, resulting in sacrococcygeal ligament injury. Sitting improperly or for a long period of time may cause continuous tension of the damaged ligaments, leading to further deepening of the damage and causing pain. 3. coccygeitis: due to fall caused by tailbone injury or chronic strain, prolonged sitting, etc., can lead to excessive friction between the tip of the tailbone and the surface of the hard objects, resulting in aseptic inflammation of the tailbone, mainly manifested as contact pain. Butt tailbone fall sitting for a long time pain may also be caused by the pelvic cavity within the genitourinary system pathology, etc., need to go to the hospital for the appropriate examination in order to clarify the cause and treatment.