Dampness of the scrotum and radiating pain at the thigh root may be caused by contact dermatitis, or it may be caused by the acute stage of scrotal eczema and genital herpes. 1. Contact dermatitis: if the scrotum area is inadvertently exposed to exogenous substances such as detergents, cleaning products, etc., it may cause contact dermatitis, which may produce erythema, edema, papules and other manifestations in mild cases, and in severe cases, the lesions may have vesicles, oozing, or even necrosis, and there may be dampness and pain in the roots of the thighs and the scrotum. 2. Scrotal eczema in the acute stage: scrotal eczema in the acute stage, in addition to intense itching, may also be accompanied by lesions such as herpes papules, small blisters, local flushing, swelling, etc., after scratching, the skin or small blisters may rupture oozing increase, easy to lead to the scrotum moist and not dry, and accompanied by radiating pain in the thigh root. 3. Genital herpes: is due to infection with herpes simplex virus, common symptoms for the external genitals or anus around the cluster or scattered small blisters, breakage after the formation of vesicles or ulcers, may be self-conscious of the pain, the pain can also be seen around the radiation. If the scrotum is moist and accompanied by radiating pain from the thigh root, you should consult a doctor in time and analyze the cause of the disease through professional examination, and then standardize the treatment after clarifying the cause of the disease.