Prospective randomized comparison of open and closed hemorrhoidectomyBackground: Grade III and IV internal hemorrhoids have a surgical indication.However there is no consensus about the best surgical procedure since all techniques have drawbacks, especially in terms of pain.Aim: To compare the results of open and closed hemorrhoidectomy.Material and Methods: Patients with grade III or IV internal hemorrhoids were randomly assigned to be treated with open or closed hemorrhoidectomy.Postoperative pain and complications were evaluated during 21 days in the postoperative period.Results: Twenty four patients were assigned to each treatment group.No differences between groups were observed for postoperative pain, complications, operative time or time required to go back to work.Ninety five percent of patients considered the ambulatory surgical procedure as good or very good.Conclusions: No differences between open and close hemorrhoidectomy were observed in this series of patients.