Pilonidal Sinus

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Day Surgery Unit – 01908 995648. 
Treatment Centre reception – 01908 995452.

What is a pilonidal sinus?

Pilonidal – a ‘nest of hairs’

Sinus tract – small abnormal channel (like a narrow tunnel) in the body. A sinus tract typically goes between a focus of infection in deeper tissues to the skin surface.
A pilonidal sinus is a sinus tract which commonly contains hairs. It occurs under the skin between the buttocks, a short distance above the anus.

Who gets pilonidal sinus?
Most cases occur in young adults or teenagers. It is rare in children and in people over the age of 40. It is much more common in men (as they are more hairy than women).
Certain factors increase the risk of developing the condition and include:
• Obesity
• Sitting a lot (sedentary occupation)
• Family history
• Previous persistent irritation or injury to the affected area.

Some people notice a painless lump in the affected area when washing; however you may not be aware that you have a pilonidal sinus. In cases where symptoms develop at some stage, these can be ‘acute’ or ‘chronic’.

Acute symptoms
You may develop increasing pain and swelling over a number of days as an infected abscess (ball of pus and surrounding skin infection) develops in and around the sinus. This can become very painful and tender.

Chronic symptoms
You may develop some pain which is less intense than the ‘acute’ symptoms. Usually, the sinus discharges some pus. This releases the pressure and so the pain tends to ease off and not become
severe. However, the infection never clears completely; so typically, the symptoms of pain and discharge can persist long-term or flare up from time to time until the sinus is treated.


Acute symptoms
Symptoms can become very painful and an emergency operation to incise (puncture) and drain the abscess is often needed.

Chronic symptoms
In most cases an operation will be advised. There are various operations which are done to cure this problem. Your surgeon will be able to give the details and the pro’s and con’s of each operation, as follows:

• Wide excision and healing by secondary intention. This operation involves cutting out the sinus, but also cutting out a wide margin of skin which surrounds the sinus. The wound is not stitched, but just left to heal by normal healing processes. The wound can take several months to heal and requires regular dressing until it heals. The advantage of this method is that all inflamed tissue
is removed and the chance of recurrence is low.
• Excision and primary closure. This means taking out the section of skin which contains the sinus. This is done by cutting the skin either side of the sinus, taking out the sinus and stitching together the two sides of the incision. The advantage of this is, if successful, the wound heals quite quickly. However, the risk of a recurrence or of developing an infection of the wound after the operation is higher than the above procedure.
• In some cases where the sinus recurs or is extensive, a plastic surgery technique may be advised to remove the sinus and refashion the nearby skin.

There are variations on the above procedures which may be suggested by your surgeon depending upon your circumstances, the size and extent of the sinus and whether it is a first or recurrent problem.

All patients who are coming for elective surgery will attend for a pre-assessment. This assessment will allow the nurse to provide a full health screen. This helps us to know that you are fit for an anaesthetic and your operation. Our main aim is to minimise the chance of your procedure being cancelled on the day of surgery.

Day of Surgery
Please follow the instructions that you are given on your appointment letter. You must not eat or drink anything or chew chewing gum before your operation. This is to make sure your stomach is empty, as it is dangerous for you to have an anaesthetic if your stomach is full. If you do not follow these instructions, your operation will be cancelled. An anaesthetist (the Doctor who looks after you when you are asleep) will come to the ward to ask some questions.

You will also be seen by a member of the surgical team who will want to ask you some questions and will obtain your consent for your operation. One of the ward nurses will also ask you some
questions. There will be many patients admitted for surgery and some waiting is to be expected. Before proceeding to theatre, a checklist will be performed and you will be asked to remove all jewellery, dentures, contact lenses, makeup and change into your gown. When it is time for your operation you will be taken to the theatre department where a member of the theatre team will meet you.

You will be asked similar questions to those you were asked on the ward, these are routine checks for your own safety. After this you will be taken into the Anaesthetic room where some
monitoring equipment will be attached to you. At this time the anaesthetic will be given to you.

After the Surgery
Following surgery you will be taken to the recovery room where you will be monitored before returning to the ward. You will normally be discharged either the same, or the following day. You may experience pain and discomfort, which can be relieved by taking painkillers. These are usually supplied for you to take home on discharge.

What are the risks?
Surgery is usually very safe and effective. However, risks and complications can occur. You need to be aware of them in order to make an informed decision about surgery. Knowing about them will also help with early detection of a problem and help with early treatment. If you are worried about anything, whether in hospital or at home, ask a member of the healthcare team. They should be able to reassure you or identify and treat any complications.

General Complications of any Operation
• Pain – occurs with every operation. Efforts will be made to minimise the pain. A local anaesthetic may be injected into the skin to ease the pain for several hours after the operation. You will be given medication to control the pain and it is important that you take it as instructed so you can move about and cough freely.
• Bleeding – can occur either during or after the operation. This rarely needs a blood transfusion or another operation, but it is common to get bruising around the area operated on.
• Infection – in the surgical wound, which needs treatment with antibiotics. This usually settles after a few days.
• Scars – a small percentage of people have an inherited tendency to scars that are unusually red and raised. This may cause an unsightly scar, but is of no further consequence.

On discharge – at home
• It is essential that you have a responsible adult to take you home, either by car or taxi.
• During the first few days you may be tired easily, but this will pass and gentle exercise is beneficial.
• It is normal to have swelling/bruising around your wound and this will settle over a week or two. However, if the area becomes hot to touch, very painful, or you are feverish, please contact your
own GP.
• Avoid heavy lifting or strenuous exercise for 1 (one) week.
• Depending upon the nature of your job you may return to work as soon as you are comfortable. This is normally about 2 weeks for a desk job and 4 weeks for a manual job.
• You must not drive for at least 48 hours after your operation due to the effects of the anaesthetic drugs. You can begin to drive when you feel comfortable and confident enough to do an
emergency stop safely. It is always best to check with your insurance company over cover as they may have their own guidelines for you to follow.
• You may resume your sex life when you are ready.
• A general anaesthetic remains in your system for 24 – 48 hours. Therefore, it is important to have a responsible adult to care for you following your operation.
• After the scar has healed, we recommend keeping the area as free of hair as possible either by shaving the area or using other hair removal techniques. After discharge, if you have any of the following problems, please contact your own GP or 111
• A temperature
• Fresh bleeding
• Redness or swelling at the operation site
• Pus or drainage from the operation site
• Prolonged or severe pain

References for the information used in this leaflet may be obtained from the author. People are unique and the alternatives, risks and benefits will of course vary from person to person. We hope this leaflet will support the information you have already received from your doctor in enabling you to make an informed decision.

If you would like further information please call:

Treatment Centre Reception
Telephone 01908 995452
…..and ask to speak to the Pre-Assessment Team.