Abdominal Wall Reconstruction (AWR)

Overview

1. Restoration of linea alba and abdominal wall anatomy
2. Creation of a dynamic, physiologic truncal muscle complex
3. Adequate prosthetic reinforcement
4. Durable, well-vascularized soft tissue coverage

• Current Surgical Therapy 14e, p. 736; Fischer's Mastery of Surgery 8e, p. 897

Surgical Anatomy

Muscle Groups

Key Tendinous Structures

• Linea alba: connects both RA complexes from xiphoid to pubic symphysis; composed of aponeuroses of EOM, IOM, TAM. Its restoration is the central goal of AWR.
• Linea semilunaris: connects the midline and anterolateral groups. Iatrogenic injury leads to major hernia and abdominal wall morbidity.
• Arcuate line of Douglas (linea semicircularis): inferior border of the posterior rectus sheath. Below this, only transversalis fascia and peritoneum form the posterior envelope.

Vascular Zones

Nerve Supply

• Current Surgical Therapy 14e, p. 736

Indications and Patient Selection

• Large midline incisional hernias (especially with loss of domain)
• Complex hernias after damage control surgery / open abdomen
• Hernias with recurrence after prior repair
• Fascial defects after tumor resection
• Enteroatmospheric or enterocutaneous fistula with associated fascial disruption

Preoperative Optimization (Mandatory)

• Sabiston Textbook of Surgery, p. 723

Surgical Techniques

1. Anterior Component Separation (ACS) - Ramirez Technique (1990)

• Large subcutaneous myocutaneous advancement flaps
• Release of the external oblique aponeurosis lateral to the semilunar line
• Allows 3-5 cm of additional length per side

2. Rives-Stoppa-Wantz Repair (Retrorectus Repair)

• The posterior rectus sheath is incised ~0.5 cm from the fascial edge of the defect
• The retrorectus plane is developed laterally to the linea semilunaris
• Lightweight macroporous synthetic mesh is placed in the retromuscular (sublay) position
• Posterior rectus sheath and peritoneum protect the bowel from direct mesh contact
• No major subcutaneous dissection - preserves neurovascular bundles and perforators

3. Transversus Abdominis Release (TAR) - Posterior Component Separation

1. Begin with retrorectus dissection to the linea semilunaris
2. Incise the posterior lamella of the internal oblique (first layer of the posterior rectus sheath) just medial to the neurovascular bundles
3. Divide the transversus abdominis muscle (upper abdomen) or its aponeurosis (mid/lower abdomen) to enter the pretransversalis plane or preperitoneal plane
4. Lateral dissection continues to at least the mid-axillary line, and can reach the psoas posteriorly
5. Superiorly: can extend under the diaphragm
6. Inferiorly: extends into the Space of Retzius, exposing the symphysis and Cooper ligament

• Mulholland and Greenfield's Surgery 7e, p. 3742-3743; Sabiston Textbook of Surgery, p. 723

Mesh Placement

Staged Management of the Open Abdomen ("Difficult Abdominal Wall")

Stage 1: Temporary Abdominal Closure (TAC)

• Techniques: Bogota bag, Wittmann patch, vacuum-assisted wound closure (VAC)
• Goals: tension-free, atraumatic, inexpensive, facilitates delayed primary closure

Stage 2: Skin Grafting / Wound Temporization

• For patients where fascial closure has failed and bowel is exposed
• Split-thickness skin graft over granulating viscera provides biological coverage

Stage 3: Definitive AWR

• Optimal timing: 6-12 months post-skin grafting, once graft has adequately separated from viscera
• Pinch test: if bowel falls away, adhesions are likely filmy and reconstruction is feasible
• Mid-portion of graft separates first; densest adhesions at the graft-musculofascial junction
• After 12 months, abdominal musculature contracts leading to progressive loss of domain

• Fischer's Mastery of Surgery 8e, p. 7526; Sabiston Textbook of Surgery, p. 719

Perioperative Considerations

Intraoperative Monitoring

• Plateau pressure: if raised >6 mmHg after closure, pulmonary complications increase 9-fold
• Bladder pressure (indirect abdominal pressure): routinely recommended when defect >600 cm²

Pain Management

• Epidural catheters and TAP blocks substantially improve postoperative pain, reduce narcotic use, improve early mobilization
• Long-acting bupivacaine (e.g., liposomal) for prolonged relief

ICG Fluorescence Angiography (FA) for Flap Perfusion

• Sensitivity 100%, specificity 91% for predicting flap necrosis
• In the only prospective RCT: intraoperative flap modification was required in 37% when FA was used vs. 4% with clinical judgment alone (p<0.001)
• ICG dose: 2.5 cc of 25 mg/10 mL solution IV; half-life 3-5 min allows repeat assessment
• Note: intraoperative modification did not translate to reduced skin necrosis rates in the RCT
• Fischer's Mastery of Surgery 8e, p. 897-898

Postoperative Care

• Incisional VAC changed at 24 hours to confirm midline viability
• Abdominal binder: throughout hospitalization and outpatient recovery
• NG tube: until true return of bowel function (avoid distension stress on repair)
• Antibiotics: 24 hours perioperatively; not needed beyond that unless contaminated field
• Early mobilization: key to success; aided by multimodal analgesia
• Drains: remove sequentially (one per side per day); remove before discharge when feasible
• Suture removal: 2 weeks in outpatient setting
• No heavy lifting for 2 months

Complications

Recent Evidence (2024-2025)

1. Open vs. robotic TAR (Lima et al., Surg Endosc 2024, PMID 39528659): Updated systematic review and meta-analysis with meta-regression comparing open and robotic transversus abdominis release for ventral hernia repair.
2. Minimally invasive posterior component separation (Tryliskyy et al., Hernia 2024, PMID 38632220): Systematic review and meta-analysis of short-term outcomes comparing MIS techniques for posterior component separation.
3. Preoperative botulinum toxin A (BTA) (Florencio de Mesquita et al., Hernia 2025, PMID 39966195): Meta-analysis of propensity-matched studies with trial sequential analysis supporting BTA injection for progressive pneumoperitoneum and lateral muscle paralysis in complex AWR - allows gradual expansion of the abdominal domain before surgery.

Summary: Technique Selection Framework

Midline defect
├─ Small-moderate, no release needed → Rives-Stoppa-Wantz (retrorectus mesh)
├─ Larger, needs more mobilization → TAR (posterior component separation + retromuscular mesh)
├─ Lateral/oblique defect or EOM release needed → Anterior component separation (endoscopic preferred)
├─ Contaminated field → Biologic or biosynthetic mesh; avoid permanent synthetic
└─ Giant defect + open abdomen → Staged repair (TAC → skin graft → delayed AWR at 6-12 months)