Pilonidal sinus disease is a condition where hairs can grow abnormally in the natal cleft or the valley between the buttocks.  Small pits can form which can get recurrently infected causing pain and discomfort.  The condition is most common in hairy men but women can also suffer from the condition.  Some patients do not suffer many symptoms and live with their condition.  Other patients suffer more and they often require an operation to excise the diseased pits.  There are many different surgical options and a specialist surgeon can tailor the treatment to the individual patient.