Referred pain in external hemorrhoids is due to: (A) Common pudendal nerve, (B) Inferior rectal nerve, (C) Splanchnic nerve, (D) Sympathetic nerve
Answer is B. Internal hemorrhoids are located on the inside lining of the rectum and cannot be felt unless they prolapse and push through the anus opening causing pain and itching. A thrombosed external hemorrhoid occurs when blood within the blood vessel clots, and may cause significant pain and swelling.