What Is Pilonidal Sinus Disease?

Pilonidal sinus and pilonidal cyst are collectively termed “pilonidal disease”—a chronic sinus tract or cyst located in the soft tissues of the natal cleft (intergluteal cleft) over the sacrococcygeal region. Its hallmark feature is the presence of embedded hair within the lesion. Clinically, it may also present as an acute sacrococcygeal abscess that ruptures to form a chronic sinus tract; alternatively, the wound may temporarily heal only to rupture again—resulting in recurrent episodes. Histologically, the cyst contains granulation tissue and fibrous proliferation, often with a tuft of hair. Although pilonidal disease may be observed shortly after birth, symptoms typically manifest during late adolescence or early adulthood (ages 20–30), coinciding with increased activity of hair follicles and sebaceous glands.

Once definitively diagnosed, surgical excision remains the primary treatment modality. However, surgery is contraindicated during active inflammation; intervention should be deferred until inflammation has fully subsided.

Several surgical techniques are available:

1. Excision with primary closure: Complete resection of all affected tissue—including surrounding muscle and skin—followed by full primary wound closure to achieve primary intention healing.

2. Partial excision with partial primary closure: Resection of the diseased tissue, followed by suturing of the lateral wound edges to the sacral fascia. This allows most of the wound to heal by primary intention, while the central portion heals secondarily via granulation tissue formation.

3. Excision with open wound management and delayed (secondary) closure: Indicated for cases with severe infection or for wounds initially closed primarily but subsequently complicated by infection requiring incision and drainage.

4. Excision with open wound management: Reserved for large wounds unsuitable for primary closure or for recurrent disease following prior surgical intervention.

5. Marsupialization: Partial excision of the sinus tract wall and overlying skin, followed by suturing of the wound edges using catgut or absorbable synthetic suture material to promote epithelialization and healing.

6. Rhomboid flap transposition: This technique effectively shortens healing time, yields excellent postoperative wound healing, and demonstrates consistently favorable clinical outcomes.