A 68-year-old man with a history of recurrent right inguinal hernia (failed Lichtenstein repair 5 years ago) presents for revision surgery. The surgeon plans a retrorectus mesh repair. During dissection, which layer must be incised to access the retrorectus space?

Explanation

## Retrorectus (Rives) Repair: Anatomical Approach The retrorectus space (also called the space of Rives) is a well-vascularized plane between the rectus abdominis muscle and its posterior sheath. This is an ideal location for mesh placement in revision hernia repair. ### Layers Encountered in Retrorectus Approach: **From Superficial to Deep:** 1. Skin and subcutaneous tissue 2. **Anterior rectus sheath** (incised) 3. **Rectus abdominis muscle** (separated/retracted, not incised) 4. **Posterior rectus sheath** (incised to enter retrorectus space) 5. Peritoneum (not breached in true retrorectus repair) ### Key Anatomical Point: The posterior rectus sheath is formed by: - **Above the arcuate line (umbilicus):** Aponeurosis of internal oblique and transversus abdominis - **Below the arcuate line:** Transversalis fascia and peritoneum only (no posterior sheath) To access the retrorectus space, the surgeon must incise the **posterior rectus sheath only**. The rectus muscle itself is gently separated and retracted medially, not incised. **Clinical Pearl:** The retrorectus space is highly vascularized (supplied by superior and inferior epigastric vessels running on the posterior rectus sheath), making it ideal for mesh integration and healing. This is why retrorectus repair has superior outcomes in revision cases. **High-Yield:** Remember: **Anterior sheath incised → Rectus separated → Posterior sheath incised → Retrorectus space entered.**