Caudal plexus pain is a clinical foreign body sensation resulting in an unpleasant and unpleasant sensation of a foreign body being trapped in the gluteal groove. It is common clinically, especially after a fall on the buttocks, and is significantly more common in women than in men. CT examination and magnetic resonance imaging (MRI) are required. Clinical manifestations 1. Depending on the cause, the nature of the pain varies greatly, from vague pain in mild cases to burning pain in severe cases, and the pain may radiate to the sacral area. The pressure pain is more obvious. 2.Foreign body sensation It is often felt as if a foreign body is caught in the gluteal groove, which is unpleasant and unpleasant. 3.Sensory disorder During examination, it can be found that the skin at the caudal anus has sensory allergy or hypoesthesia, but it is rare that the sensation disappears completely. Examination 1.Anal diagnosis is helpful to determine the status of the sacrococcygeal area, including understanding the muscle tone and pressure pain of the anal sphincter. 2.X-ray plain film or MRI examination can show the status of sacrococcygeal bone and the nature of lesion.