What is pilonidal sinus?
Pilonidal sinus is a chronic infection of the sacrococcygeal area, characterised by the presence of one or more pits in the natal cleft, with hair and skin debris trapped under the skin. It causes chronic inflammation, abscesses and chronically draining fistulas.
It is classified as acute (abscess) and chronic (with persistent sinus tracts). Modern treatment aims to definitively remove the inflammatory tissue with the lowest possible recurrence rate and rapid recovery.
How common is it?
Pilonidal disease has an incidence of approximately 26 cases per 100,000 population per year. It affects mainly young adults aged 15–30 years, with marked male predominance (3:1). It is rare after age 45.
The condition has been called "jeep disease" because of its high frequency among American soldiers in World War II — long hours of sitting and friction contributed to its appearance.
How does it present?
The main symptoms of pilonidal sinus include:
- Pain, swelling and redness in the sacrococcygeal area, often acute in abscess.
- Chronically draining fistula with purulent or serosanguinous discharge.
- Foul-smelling discharge.
- Visible pits in the midline of the natal cleft.
- Local fever and tenderness.
- Difficulty sitting and limitations in daily activities.
- In long-standing disease: multiple sinus tracts and skin discoloration.
How is it diagnosed?
Diagnosis is purely clinical:
- Inspection of the sacrococcygeal area with identification of pits in the midline.
- Evaluation of the extent of disease (single pit vs. complex disease with multiple tracts).
- Differential diagnosis from perianal abscess, hidradenitis suppurativa, fistula in ano.
- In recurrent or complex cases: MRI for accurate mapping of sinus tracts.
- Microbiological culture in active infection.
Which factors increase risk?
There is some familial predisposition (~38% of patients have positive family history), but acquired factors predominate.
- Male sex (3 times more common).
- Young age (15–30 years).
- Hirsutism (abundant hair growth in the area).
- Obesity, deep natal cleft.
- Prolonged sitting (drivers, students, office workers).
- Sweating, poor local hygiene.
- Friction from clothing or activities (cycling, riding).
- Family history of pilonidal disease.
Modern therapeutic options
The choice of the appropriate technique is individualised for each patient, based on disease extent, prior recurrences, anatomy and patient preference. The modern trend is towards minimally traumatic techniques with rapid return to activity.
Abscess Drainage
For acute pilonidal abscess. A small incision in the lateral position (not midline) for drainage of pus. Definitive surgery is performed after resolution of inflammation, usually 6–8 weeks later. About 40% of patients may not need further surgery.
Sinusectomy / EPSiT
Minimally invasive techniques for simple disease. Sinusectomy involves precise excision of pits and small sinus tracts. EPSiT (Endoscopic Pilonidal Sinus Treatment) uses an endoscope for sinus visualisation and ablation. Rapid recovery, excellent cosmetic result.
Karydakis Flap
Gold standard for chronic disease. Eccentric excision with movement of a lateral flap, eliminating the midline cleft. Recurrence rate <5%. Hospital stay 1–2 days with primary wound healing in 2–3 weeks.
Limberg Flap
For complex disease, recurrence, or after failure of other techniques. Rhomboid excision with rotation flap from the gluteal area. Excellent results in difficult cases, low recurrence rate (<3%).
Laser treatment (SiLaC / EPSiT)
Modern minimally invasive technique. A laser fiber controllably ablates the sinus tract wall, without tissue excision or sutures. Minimal postoperative pain, excellent cosmetic result, rapid return to activities — ideal for patients who wish to avoid extensive surgery.
Frequently asked questions
Can the condition recur after surgery?
With modern techniques (Karydakis, Limberg), recurrence is <5%. With older techniques (open wound, simple excision), recurrence can reach 30–40%. For prevention, hair removal in the area and meticulous local hygiene are very important.
Will I have a long incision?
With minimally invasive techniques (sinusectomy, EPSiT), incisions are small (<2cm). With flap techniques (Karydakis, Limberg), the incision is larger but cosmetically acceptable. All techniques aim for the best possible cosmetic result.
Will laser hair removal in the area help?
Yes. Laser hair removal in the sacrococcygeal area reduces recurrence rate significantly. Recommended after surgery and continued for 1–2 years. Modern laser technologies offer effective and painless treatment.
How quickly can I return to my activities?
With minimally invasive techniques, return to office work in 7–10 days. With flap techniques, recovery takes 2–4 weeks. Driving is possible from the next day with sinusectomy and after 1 week with flap techniques.