Thrombosed external haemorrhoids are a common and painful acute perianal condition. Management options include conservative treatment, an office procedure or referral for surgery.
Thrombosed external haemorrhoids are actually perianal thromboses within perianal subcutaneous veins (external haemorrhoidal plexus), and may occur with or without rupture of the veins. They occur in younger patients, often in their thirties, and are caused by straining, often in association with hard faeces, and less often with diarrhoea. They also occur late in pregnancy (8%) and postpartum (20%), and are seen (though rarely) after rubber band ligation of internal haemorrhoids or stapled haemorrhoidectomy.