The unpleasant and unpleasant sensation of a foreign body in the gluteal sulcus is clinically common, especially after a fall on the buttocks, and is significantly more common in women than in men. The caudal plexus nerve composed of sacral 5, caudal 1 and some of the anterior branches of sacral 3 and 4 nerves mostly coincides with the fibers below the paravertebral sympathetic nerve trunk. Prevention note: 1, adjust daily life and workload, regular activities and exercise, avoid strain. 2, maintain emotional stability, avoid emotional excitement and tension. 3.Keep the bowel movement smooth, avoid forceful bowel movement, eat more fruits and high-fiber food. 4.Avoid cold stimulation, pay attention to keep warm.