A pilonidal sinus is a small hole or tunnel in the skin that can easily become infected. It typically forms in the cleft at the top of the buttocks. When a pilonidal sinus becomes infected it can turn ...

Pilonidal sinus—also called a pilonidal cyst—is a skin infection that occurs in or around the crease of your buttocks. This condition happens when hair, skin cells, and dirt clog a hair follicle, ...

Pilonidal cysts typically develop above the cleft of the buttocks. These swollen lumps contain hair or other debris. They occur when small holes in the skin, known as pilonidal sinuses, become ...

A pilonidal sinus is a small tunnel that develops at the top of the crease in the buttocks. Trapped hair around the buttocks crease can lead to an abscess, and a pilonidal sinus may develop as a ...