The papules on the buttocks may be folliculitis, which stimulates the proliferation of fibroblasts to form scars during the healing process, especially those with scar constitution are more prone to hard papules and last for a long time. Among them, scar is the general name of the appearance, morphology and histopathological changes of normal skin tissue caused by various trauma, and it is an inevitable product in the process of human wound repair. When scar growth exceeds a certain limit, various complications will occur. At the same time, scars are different from normal skin, rough and pigmented.