Overview
Definition:
A pilonidal sinus is an acquired condition characterized by a chronic inflammatory process in the sacrococcygeal region, typically presenting as one or more epithelialized tracts with associated pits, most commonly originating from hair follicles in the natal cleft
The Bascom cleft lift procedure is a surgical technique designed to excise the sinus tract and surrounding unhealthy tissue while flattening the natal cleft to reduce the recurrence rate.
Epidemiology:
Pilonidal sinus is most prevalent in young adults, with a predilection for males (2-4 times more common than females), typically presenting between the ages of 15 and 35 years
Risk factors include obesity, sedentary lifestyle, deep natal clefts, and hirsutism
It is more common in Caucasians.
Clinical Significance:
Pilonidal sinus can cause significant morbidity due to pain, recurrent infections, drainage, and potential for delayed healing
Effective surgical management is crucial to provide lasting relief and prevent complications
The Bascom cleft lift is considered a superior technique for reducing recurrence compared to traditional excisional methods due to its emphasis on eliminating the anatomical predisposing factor.
Clinical Presentation
Symptoms:
Asymptomatic midline pits or sinus openings in the sacrococcygeal region
Acute infection presenting as a painful, tender abscess with surrounding erythema and swelling
Chronic drainage of seropurulent or bloody material from the sinus opening
Recurrent episodes of pain and inflammation
Low-grade fever during acute infections.
Signs:
Visible midline pits or sinus openings just superior to the anal verge, typically in the natal cleft
Palpable induration around the sinus tract, especially when infected
Erythema, tenderness, and fluctuance if an abscess is present
Purulent or serosanguineous discharge from the openings
In chronic cases, granulation tissue may be visible.
Diagnostic Criteria:
Diagnosis is primarily clinical, based on characteristic physical examination findings in the sacrococcygeal region, often confirmed by patient history of intermittent drainage or recurrent infections
Imaging is usually not required for uncomplicated cases but may be used to delineate complex tracts or rule out other pathologies.
Diagnostic Approach
History Taking:
Detailed history of onset, duration, and character of symptoms
Previous episodes of infection, drainage, or surgical intervention
Nature of discharge (serous, purulent, bloody)
Association with sitting, standing, or physical activity
Risk factors such as occupation (sedentary jobs), obesity, hirsutism, and family history
Red flags include signs of systemic infection, perirectal abscess, or suspicion of underlying malignancy (rare).
Physical Examination:
Examination of the sacrococcygeal region in prone or lateral decubitus position
Inspection for midline pits, sinus openings, erythema, swelling, and discharge
Palpation for tenderness, induration, and fluctuance
Digital rectal examination to rule out anal canal pathology and assess for perirectal extension.
Investigations:
Generally not required for uncomplicated pilonidal sinus
If there is suspicion of complex anatomy, a sinus tractogram may rarely be performed
In cases of recurrent or non-healing sinuses, biopsy for histopathological examination can rule out other conditions like hidradenitis suppurativa or squamous cell carcinoma (rare).
Differential Diagnosis:
Perianal abscess
Hidradenitis suppurativa
Pilonidal cyst (congenital)
Dermoid cyst
Spinal lipoma or meningocele (occult spinal dysraphism)
Furuncle
Anal fissure
Pilonidal disease can sometimes be misdiagnosed as a perianal abscess or other perianal dermatological conditions.
Management
Initial Management:
For acute abscess: incision and drainage (I&D) of the abscess is the primary step
Antibiotics may be used for cellulitis or systemic signs of infection, but I&D remains the definitive treatment for the abscess itself.
Medical Management:
Primarily for managing acute infection and associated cellulitis
Antibiotics such as clindamycin, metronidazole, or cephalexin can be prescribed
However, antibiotics alone do not treat the underlying sinus tract and are not a substitute for surgical intervention for definitive management.
Surgical Management:
The Bascom cleft lift procedure is indicated for symptomatic, recurrent, or complicated pilonidal sinuses
The technique involves excising the sinus tract and pits, creating a wider, shallower cleft by lifting the flaps and suturing them laterally to the fascia, thereby eliminating the deep midline sulcus that predisposes to recurrence
This approach aims for primary closure with reduced tension.
Postoperative Care:
Wound care is crucial, involving regular cleaning and dressing changes to prevent infection and promote healing
Patients are advised to avoid prolonged sitting and strenuous activity for several weeks
Hair removal in the natal cleft area postoperatively is recommended to reduce recurrence
Pain management with analgesics is provided
Early ambulation is encouraged.
Complications
Early Complications:
Wound infection: typically cellulitis or superficial wound dehiscence
Seroma formation
Hematoma
Pain and discomfort
Anesthesia-related complications.
Late Complications:
Recurrence of pilonidal sinus: the main concern, although significantly reduced with cleft lift
Chronic wound healing problems or sinus tract formation
Scar hypertrophy or keloid formation
Persistent pain
Nerve irritation or injury (rare).
Prevention Strategies:
Meticulous surgical technique by the surgeon
Adequate excision of all sinus tracts and diseased tissue
Achieving a wide, flattened natal cleft
Tension-free closure
Postoperative hair removal in the natal cleft
Maintaining good hygiene
Avoiding prolonged sitting and obesity.
Prognosis
Factors Affecting Prognosis:
The extent and complexity of the sinus tract
The presence of chronic infection or previous failed surgeries
The patient's adherence to postoperative care instructions, particularly regarding hair removal and avoiding pressure
The surgeon's experience with the cleft lift technique.
Outcomes:
The Bascom cleft lift procedure has demonstrated significantly lower recurrence rates compared to traditional excisional techniques, often cited as less than 5-10%
Successful healing leads to resolution of symptoms and improved quality of life
Most patients can return to normal activities within 2-4 weeks.
Follow Up:
Regular follow-up appointments are recommended, typically at 2-4 weeks postoperatively to assess wound healing, followed by visits at 3-6 months and then annually for the first 1-2 years, or as needed
This allows for early detection of any signs of recurrence or complications and reinforcement of preventive measures.
Key Points
Exam Focus:
Understand the pathophysiology of pilonidal sinus and the rationale behind the Bascom cleft lift procedure
Differentiate between acute and chronic presentations
Key surgical steps and principles of wound closure
Recurrence rates and factors influencing them.
Clinical Pearls:
The Bascom cleft lift transforms a deep natal cleft into a wide, shallow one, thereby reducing the likelihood of hair and debris accumulation
Adequate excision of all sinus tracts, including offshoots, is paramount
Hair removal in the natal cleft is a vital long-term preventive measure.
Common Mistakes:
Incomplete excision of sinus tracts
Failure to flatten the natal cleft adequately
Excessive tension on the closure sutures, leading to dehiscence
Not emphasizing postoperative hair removal
Misdiagnosing pilonidal sinus as a simple perianal abscess.