What is the management approach for a pilonidal sinus?

Management of Pilonidal Sinus

For acute pilonidal abscess, aspiration with antibiotics is the preferred initial approach (95% effective), converting the emergency into an elective procedure and allowing patients to return to normal activities the next day, followed by definitive excision with off-midline primary closure weeks later. 1

Acute Pilonidal Abscess Management

Initial Treatment - Aspiration Protocol

• Perform aspiration under local anesthetic using a wide-bore needle to drain the abscess cavity to dryness on the same day of presentation 1
• Send samples for microbiology and initiate empirical oral antibiotics covering both anaerobes and aerobes 1
• This approach is effective in 95% of cases (38/40 patients) and allows patients to return to normal activities the following day 1
• Review within 5-7 days to assess response and plan definitive treatment 1

Criteria for Aspiration Approach

• Patient must not be septic, immunocompromised, or diabetic 1
• No skin necrosis present 1
• If aspiration fails (5% of cases), proceed with incision and drainage 1

Alternative Acute Management

• Incision with drainage followed by controlled excision using loop diathermy allows one-stage definitive management of both acute abscess and chronic sinuses 2
• Unroofing and curettage demonstrates superior outcomes compared to simple drainage, with 96% healing rate versus 78.7% and recurrence of only 11% versus 42% 3

Definitive Surgical Management

Timing of Elective Surgery

• Schedule definitive excision at median of 9 weeks after successful aspiration when acute inflammation has completely resolved 1
• Traditional recommendation is 4-8 weeks after initial drainage 3

Surgical Technique Selection

Off-midline closure is superior to midline closure and should be the standard when primary closure is desired. 4

Off-Midline Primary Closure (Preferred)

• Demonstrates significantly lower infection rates (RR 0.21; 95% CI 0.09 to 0.52) compared to midline closure 4
• Recurrence rate is 80% lower (Peto OR 0.20; 95% CI 0.09 to 0.46) than midline closure 4
• Fewer complications overall (RR 0.11; 95% CI 0.03 to 0.48) 4

Open Healing vs Primary Closure Decision

• Open healing has 58% lower recurrence risk (RR 0.42; 95% CI 0.26 to 0.66) compared to primary closure 4
• Primary closure allows return to work 10.5 days earlier (95% CI 5.75 to 15.21 days) 4
• No difference in infection rates between open and closed techniques 4
• Healing is more rapid with primary closure 4

Avoid Midline Closure

• Midline primary closure shows 4.7-fold higher infection rate (95% CI 1.93 to 11.45) 4
• Nearly 5-fold higher recurrence rate (Peto OR 4.95; 95% CI 2.18 to 11.24) 4
• 9-fold increase in other complications (RR 8.94; 95% CI 2.10 to 38.02) 4

Postoperative Management

Wound Care

• Daily sitting in warm tub with douche recommended for open wounds 3
• Most patients spend only one day in hospital 3
• Patients typically return to work 7-10 days after treatment 3

Expected Healing Timeline

• Initial healing occurs in less than 2 months for most patients 3
• Wounds not healing within 10 weeks require reassessment 3

Key Clinical Pitfalls

Common Errors to Avoid

• Do not perform midline primary closure - this is associated with the worst outcomes across all metrics 4
• Simple incision and drainage alone has greater than 40% recurrence rate 3
• Avoid attempting definitive surgery during acute abscess phase in non-selected patients 1
• Do not discharge patients after aspiration without arranging follow-up within 7 days 1

Recurrence Recognition

• A recurrent abscess at a previous pilonidal site may indicate inadequate initial treatment requiring definitive excision 5
• Incision and drainage should be performed for recurrent abscesses 5