Bumps at the base of the thighs may be caused by sebaceous cysts, boils, inguinal hernias, and enlarged inguinal lymph nodes. 1. Sebaceous cysts: Sebaceous cysts are usually formed when sebaceous glands are blocked and secretions accumulate, and usually appear as subcutaneous nodules. The center of the cyst may have a black, pinpoint-sized opening for the ductal opening of the blocked sebaceous gland. 2. Boil: It is a purulent inflammation caused by bacterial infection, with symptoms of redness, swelling and pain. After rupture, yellowish-white pus can be discharged, and the symptoms can gradually subside after discharge. 3. Inguinal hernia: It is a kind of extra-abdominal hernia caused by various reasons, manifested by a slight swelling sensation, which may be accompanied by distension and drawing pain. 4. Enlarged inguinal lymph nodes: If the organism has infections, metabolic reactions, tumors and other diseases, it is very likely that the lymph nodes in the groin will be enlarged. Thigh root lumps have more reasons, if the root of the thigh has an unknown cause of the lumps, it is recommended to go to the hospital in a timely manner, to identify the specific causes of targeted treatment.