Incisional Hernia Repair - Steps

Pre-operative Optimization ("Prehabilitation")

• Weight loss - loss of 5 kg creates ~1 extra litre of abdominal space; 7% total body weight loss significantly improves metabolic state
• Smoking cessation
• Fitness improvement and core strength exercises
• Nutritional optimization if malnourished
• Multidisciplinary team assessment is becoming standard for complex hernias
• Foley catheter and orogastric tube placed at the start for bladder/stomach decompression

A. Open Primary Repair (Small Hernias <2 cm)

1. Incision - Made to extend past the hernia defect
2. Adhesiolysis - Free the anterior abdominal wall completely; improves mobilization and medialization of abdominal musculature
3. Bowel inspection - Check for any injury and repair as needed; full enterolysis only if preoperative bowel obstruction symptoms
4. Fascial edge clearance - Clear fascial edges of extraneous fat and muscle
5. Fascial closure - Running suture with the "small-bite technique" (STITCH trial): 5 mm bites, 5 mm apart, using 2-0 slowly resorbable monofilament on a 30-40 mm needle; suture-to-wound-length ratio must be ≥4:1
6. For wide midline defects: interrupted figure-of-eight sutures placed loosely first along entire wound, then cinched and tied to distribute tension evenly

B. Open Mesh-Based Repair (Larger/Recurrent Hernias)

Step 1 - Patient Positioning and Setup

• Supine, arms out
• Foley catheter + orogastric tube for decompression

Step 2 - Incision and Access

• Abdominal incision extended past the hernia defect on all sides

Step 3 - Adhesiolysis

• Complete lysis of adhesions from the anterior abdominal wall
• Avoid peritoneal injury
• Remove any prior intraperitoneal mesh (reduces infection and fistula risk)
• Protect viscera with a large countable laparotomy towel

Step 4 - Bowel Inspection

• Inspect bowel for injury; full enterolysis if obstruction symptoms were present preoperatively

Step 5 - Mesh Placement (choose position based on defect size and tissue quality)

Step 6 - Fascial Closure

• Midline fascia closed before mesh placed in sublay position
• Wide overlap of mesh on all sides of the defect (at least 3-5 cm)

C. Myofascial Release / Component Separation (for Large/Complex Defects)

External Oblique Release (Anterior Component Separation - Ramirez)

1. Create skin/subcutaneous flaps over anterior rectus sheath, lateral to the rectus muscle
2. Incise posterior rectus sheath just lateral to linea alba; separate rectus from posterior sheath
3. Incise external oblique aponeurosis lateral to the linea semilunaris, from costal margin to iliac crest
4. Separate external oblique from underlying internal oblique muscle
5. Close midline fascia with reduced tension; each side gains 3-8 cm of advancement

Transversus Abdominis Release (TAR - Posterior Component Separation)

1. Enter retrorectus space (incise medial posterior rectus sheath)
2. Develop retrorectus plane bilaterally
3. At the linea semilunaris, divide the transversus abdominis (TA) muscle using a right-angle dissector and electrosurgery
4. Dissect laterally in a bloodless plane to the retroperitoneum/psoas border
5. Connect bilateral spaces via midline preperitoneal dissection
6. Extend superiorly to subxiphoid space and inferiorly to Retzius/Bogros space as needed
7. Close posterior sheath, place large uncoated mesh in retromuscular space, close anterior fascia

D. Laparoscopic / Robotic Repair

IPOM (Intraperitoneal Onlay Mesh)

1. Establish pneumoperitoneum; place laparoscopic ports (triangulate ports around target)
2. Reduce hernia contents, lyse adhesions
3. Identify all hernia defects
4. Optionally close the defect transabdominally with sutures
5. Place barrier-coated mesh intraperitoneally with adequate overlap (≥3-5 cm)
6. Secure mesh with tacks and/or transfascial sutures

eTEP (Extended Totally Extraperitoneal) / Retromuscular Approach

1. Optical entry directly into the retrorectus space (port through rectus muscle, just superficial to posterior sheath)
2. Develop retrorectus space
3. Perform "crossover maneuver" - incise medial posterior sheath ~0.5 cm from linea alba to connect bilateral retrorectus spaces through midline preperitoneal corridor
4. Develop contralateral retrorectus space
5. Oppose ports placed as needed
6. Approximate hernia defect with absorbable barbed suture; plicate linea alba if necessary
7. Place uncoated mesh in retromuscular space
8. Close posterior layer (approximate posterior rectus sheaths or bridge with peritoneum)

E. Key Principles Throughout

• Mesh overlap of at least 3-5 cm on all sides of defect
• Suture-to-wound-length ratio ≥ 4:1 for any primary closure
• Avoid inlay (bridging) mesh in elective settings - high recurrence
• Remove old intraperitoneal mesh when safe to do so
• Bowel protection at all times - towel over viscera before closure
• Close peritoneal defects with resorbable suture if created during dissection