What are the surgical steps for Limberg flap reconstruction in a patient with pilonidal sinus?

Surgical Steps for Limberg Flap Reconstruction in Pilonidal Sinus

The Limberg flap procedure involves rhomboid excision of the pilonidal sinus followed by transposition of a fasciocutaneous flap from the gluteal region to obliterate the midline cleft and achieve primary closure. This technique has demonstrated excellent outcomes with recurrence rates of 2-4.8% and low complication rates in multiple studies 1, 2, 3, 4, 5.

Preoperative Preparation

• Anesthesia: The procedure can be performed under either general or regional (spinal) anesthesia 2, 5.
• Prophylactic antibiotics: Administer prophylactic antibiotics preoperatively 1.
• Patient positioning: Position the patient prone with the buttocks taped apart to expose the sacrococcygeal area.

Surgical Technique

Step 1: Marking and Planning

• Mark the rhomboid excision: Design a rhomboid shape around the pilonidal sinus with all margins at least 1-2 cm from the sinus openings 1, 2.
• Plan the Limberg flap: Mark the transposition flap from the gluteal region, ensuring the flap design will move tissue away from the midline 3.
• The rhomboid should have angles of 60° and 120° to allow proper flap transposition 2.

Step 2: Excision

• Perform en bloc excision: Excise all sinus tracts completely in a rhomboid fashion down to the presacral fascia 2, 3.
• Ensure adequate depth: The excision must include all epithelialized tracts and reach healthy tissue at all margins 1.
• Verify complete removal: Inspect the specimen to confirm all sinus tracts have been removed 2.

Step 3: Flap Preparation

• Create the Limberg flap: Prepare a fasciocutaneous transposition flap from the gluteal region lateral to the defect 3, 5.
• Include adequate tissue: The flap must include skin, subcutaneous tissue, and fascia to ensure viability 3.
• Maintain proper dimensions: The flap should be designed to fill the defect completely without tension 2.

Step 4: Flap Transposition

• Rotate the flap: Transpose the flap into the defect to obliterate the midline cleft 3.
• Ensure the flap moves tissue laterally: This is critical to flatten the natal cleft and prevent recurrence 3.
• Verify adequate blood supply: Check for good capillary refill in the flap before securing 1.

Step 5: Closure and Drainage

• Place suction drain: Insert a closed suction drain beneath the flap to prevent seroma formation 1, 2.
• Close in layers: Suture the deep fascia first, then subcutaneous tissue, and finally skin 2.
• Ensure all suture lines are off the midline: This prevents wound breakdown and recurrence 3.
• Achieve tension-free closure: The flap should lie flat without any pulling on the suture lines 2.

Postoperative Management

• Hospital stay: Average hospital stay is 3-4.5 days 2, 4, 5.
• Drain removal: Remove the suction drain when output is minimal, typically within 2-4 days 1.
• Return to activity: Patients typically return to full activity in 10-25 days (mean 12.8-18.8 days) 2, 4.
• Wound care: Keep the area clean and dry; avoid prolonged sitting in the early postoperative period 5.

Key Technical Points and Pitfalls

• Complete excision is mandatory: Incomplete removal of sinus tracts is a primary cause of recurrence 2, 3.
• Flattening the natal cleft is essential: The flap must effectively obliterate the midline depression to prevent hair accumulation and new sinus formation 3.
• Avoid tension on the flap: Excessive tension leads to wound dehiscence and flap necrosis 1, 4.
• Suction drainage reduces complications: Use of closed suction drainage decreases seroma formation (1.5-2% with drain vs higher without) 2, 4.

Expected Outcomes

• Recurrence rate: 2-4.8% in large series 2, 3, 4, 5.
• Wound complications: Minor wound infection occurs in 1.5-7% of cases 2, 3.
• Flap necrosis: Minimal flap necrosis occurs in only 3-4.1% of patients 2, 4.
• Seroma formation: Occurs in 1.5-2% of cases 2, 4.
• Primary healing: Achieved in over 99% of patients 3.

Advantages Over Other Techniques

• Suitable for complex and recurrent disease: The Limberg flap is particularly effective for extensive sinus tracts and cases where simpler operations have failed 1, 5.
• Low recurrence rate: Significantly lower than excision with healing by secondary intention 2, 3.
• Quick return to normal activity: Faster than open healing techniques 4, 5.
• Eliminates predisposing factors: By flattening the natal cleft and moving tissue off the midline 3.