Pilonidal Sinus

Means a nest (‘nidus’) of hairs (‘pilus’)

Accumulates in the natal cleft above the anus between the buttocks.

The hair gets under the skin through little pits and causes infection.

The infection then forms an abscess or discharges.

If hairs remain, there may be a chronic discharge of fluid and pus into the cleft via what is termed a sinus – thus pilonidal sinus.

A sinus is a blind ending tract.

Occasionally this type of condition can occur elsewhere such as in the umbilicus or in Hairdresser’s hands and fingers


For a small abscess causing severe pain – can be drained in the office under local anaesthetic.  May not cure the problem but relieves the symptoms

A more formal operation to excise the whole area may be required later to prevent recurrence

A larger abscess may need treatment in the operating theatre under general anaesthesia

For a chronic sinus the usual treatment is wide excision under under general anaesthesia in hospital

At the time of operation for a chronic sinus, a decision is made as to whether to leave the wound open with a pack or to close with sutures.

The main problem with this condition, apart from being painful and annoying, is that there is a high recurrence rate following surgery.