OverviewA pilonidal dimple is a small pit or sinus in the sacral area just at the top of the crease between the buttocks. The pilonidal dimple may also be a deep tract, rather than a shallow depression, leading to a sinus that may contain hair. During adolescence the pilonidal dimple or tract may become infected forming a cyst-like structure called a pilonidal cyst. These pilonidal cysts may require surgical drainage or total excision to prevent reinfection.
Update Date 11/10/2013
Updated by: Susan Storck, MD, FACOG, Chief, Eastside Department of Obstetrics and Gynecology, Group Health Cooperative of Puget Sound, Bellevue, Washington; Clinical Teaching Faculty, Department of Obstetrics and Gynecology, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Bethanne Black, and the A.D.A.M. Editorial team.