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Medical Encyclopedia

Pilonidal cyst and dimple

A 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.