What is it and how did I get it?

Pilonidal sinus disease is a condition characterized by the presence of hair shafts within the subcutaneous fat (underneath the skin) between the buttocks, an area sometimes called the natal cleft. The presence of hair shafts in this abnormal location induces a strong inflammatory reaction and often episodes of infection leading to abscess formation (Pilonidal abscess). Symptoms vary from the presence of sinuses without symptoms to recurrent abscess formation, bleeding and ongoing discharge from an open non healing wound. The condition is commoner in people of southern European origin and in those who have a hairy back. A family history of the condition is not uncommon.

Rhomboid flap for pilonidal sinus disease

The rhomboid flap is a technique that has a high success rate in the excision and primary closure of this condition. The key features of this operation are that the deep natal cleft is obliterated and that there are no surgical scars in the midline where recurrence can be a problem with other surgical techniques. (See the diagram on the attached sheet).

 In the operation a diamond shaped piece of skin and fat is excised and adjacent tissue is rotated to fill the defect. A suction drain is left in overnight and the skin incision is closed with absorbable (dissolving) sutures.

Before the operation

The whole area op the surgery needs to be hair free. Never shave the area. Please visit a hair removal clinic for a wax in the week prior to the operation:



Wax’n’laser Midland - Wellington

(04) 499 5859


Level 1 39 Johnston Street, Wellington
(Johnston St. is off Lambton Quay between Kirks & Midland Park)


What can I expect after my operation?

The operation is performed under a general anaesthetic and takes about 45 minutes to perform. Long acting local anaesthetic is placed in the operative site at completion of the surgery and will reduce pain for the first 24 hours. A small suction drain is left in overnight and taken out before you leave hospital the next morning. You will only need oral painkillers on discharge from hospital for a few days.

Care of the wound

It is important to keep the wound socially clean and dry during the first ten days after the operation. You may shower but lightly dab the wound dry afterwards and if possible dry it with a hair dryer on cold blow. Steristrips will be placed on the wound in addition to the dissolving sutures.

 Please have the wound checked by my nurse at Southern Crossone week after the surgery. Healing is usually fast and the recurrence rate is very low! After ten days if the wound is looking good you can resume nearly all activities.

Please start to use a depilatory cream (“Veet” or “Nair” shower cream) ten days after the operation to cover the area down to the anal canal. Cream should be applied every two weeks 10 minutes before a morning shower. This should be done for two to three months to prevent hair ingrowth into the scar until it is mature.


“Informed consent for surgery is a process not a piece of paper”. If you need more information about your proposed treatment please don’t hesitate to ask.

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