Pilonidal Disease

Pilonidal disease affects the skin at the top of the crease between your buttocks — a region doctors call the natal cleft — near the tailbone (sacrococcygeal area). The condition is caused by loose hairs that penetrate the skin and act like a splinter, triggering inflammation and a foreign body reaction. This leads to the formation of cysts, sinuses (small tunnels that burrow under the skin), and recurring painful infections. The name comes from the Latin words for "hair" (pilus) and "nest" (nidus) — a hair-nest beneath the skin. It most commonly affects younger men, particularly those with dark, coarse hair, a deep natal cleft, or jobs that involve a lot of sitting. You have not caused this through poor hygiene — it is simply an unfortunate combination of anatomy and hair type.

Acute pilonidal abscess: a swollen, intensely painful lump at the top of the buttock crease that feels hot and tense. It may discharge pus, and the surrounding skin is often red and inflamed. This is the form that usually brings people to the doctor or emergency department urgently. Pilonidal sinus: a chronic condition where one or more small openings remain in the skin of the natal cleft after a previous abscess or surgery. These sinuses can discharge intermittently, cause a dull aching pain while sitting, and flare into full abscesses from time to time.

For an acute abscess: the most pressing need is to drain it — this is done under local or general anaesthetic and gives immediate pain relief. However, drainage alone does not solve the underlying problem. About half of people who have an abscess drained will go on to develop a chronic sinus that keeps causing trouble, and in those cases a definitive operation is needed.

For chronic or recurrent pilonidal disease: surgery to remove the sinus and affected tissue is the definitive answer. There are several surgical techniques, and the right choice depends on your situation. The simplest option is wide excision with the wound left open to heal gradually on its own (called healing by secondary intention). This works, but the wound in this location can take 6–12 weeks to fully heal and typically requires daily dressing changes throughout — sometimes with a special vacuum pump (VAC) device to help the wound close. Flap procedures — such as the Karydakis flap, Bascom's cleft lift, or rhomboid (Limberg) flap — take a different approach: the surgeon rearranges the nearby skin to close the wound primarily, the way a zip is closed. Flap repairs typically heal within 3–4 weeks with far fewer dressing changes, and they have a lower chance of the condition coming back. For most patients, particularly younger people returning to work or study, this is the preferred option.

As for hair removal: routine shaving or hair removal of the natal cleft is not recommended as a standard first step. If your condition recurs or your individual situation makes it appropriate, laser hair removal in the natal cleft area may be advised — laser is preferred over regular shaving in those cases. This is something Mr Nguyen will discuss with you specifically at your consultation.

Unfortunately, pilonidal disease can come back after surgery — this is a recognised risk with all surgical techniques, not just the simpler ones. The risk is lowest with flap procedures. Keeping the area clean, maintaining a healthy weight, and avoiding prolonged sitting while the wound heals all help reduce the chances of it returning.

For chronic and recurrent pilonidal disease, Mr Nguyen's preference is a flap closure — either a Karydakis flap, cleft lift, or rhomboid flap — because these techniques avoid the burden of a prolonged open wound and have the lowest known recurrence rates. That said, the right approach is always individualised. At your consultation, Mr Nguyen will discuss your specific disease pattern, any previous surgery, your body shape, and your recovery needs before recommending a technique. There is no single answer that suits everyone.

If you have a painful, swollen lump developing at the top of your buttock crease — especially if it feels hot and is getting worse quickly — that is an abscess and needs draining urgently. Do not wait for it to burst on its own. If you have a sinus that keeps discharging or recurring infections, or if you have already had surgery that has not resolved the problem, a specialist assessment will help work out the best path forward.

For an acute abscess, your GP may send you directly to hospital for incision and drainage — this is the immediate priority and gives prompt relief. For chronic or recurrent disease, your GP will send a referral and most patients are seen within one to two weeks. At the consultation, Mr Nguyen will examine the area, ask about the pattern of flare-ups, and discuss the options in detail.

Pilonidal treatment is often staged. If the area is acutely inflamed, simple drainage comes first and definitive surgery is planned a few weeks later once the tissues have settled — operating on inflamed tissue gives a poorer result. The definitive operation is usually a flap closure (Karydakis, cleft lift, or rhomboid flap) chosen to suit your anatomy and recovery needs. A follow-up appointment is arranged a few weeks afterwards to check healing, and Mr Nguyen will give clear advice on hair management and hygiene to reduce the risk of recurrence.

Mr Ba Nguyen consults at his rooms in Heidelberg and operates at Warringal Private Hospital, Heidelberg, and Epworth Eastern, Box Hill. A GP or specialist referral is required.