Pilonidal Sinuses
Pilonidal sinus is a condition found in the midline posteriorly, between the buttocks, in the cleft overlying the tailbone. There are one or more midline pinpoint openings, which may or may not be infected and which communicate under the skin with a cavity which is lined by granulation tissue and which may contain hair lying loosely or in tufts.It is a condition which can exist in the noninfected state or there may be infection with abscess formation.