Components Separation Technique — Large Ventral Hernia

Components separation technique (CST), originally described by Ramirez in 1990 and modified into the transversus abdominis release (TAR) by Novitsky, is an anatomic abdominal wall reconstruction that mobilizes the rectus muscle complex by releasing key fascial layers. Anterior CST releases the external oblique aponeurosis 1-2 cm lateral to the linea semilunaris, providing approximately 8-10 cm of medial advancement per side at the level of the umbilicus.

Posterior components separation, particularly TAR, releases the transversus abdominis muscle in the retromuscular plane, creating a wide pocket for sublay mesh placement while preserving the linea semilunaris. TAR provides 12-15 cm of bilateral medial advancement, allowing closure of defects up to 30 cm in width. It also preserves intercostal nerve innervation, reducing risk of bulging and lateral muscle atrophy compared with anterior CST.

Indications include giant ventral hernia (W3 EHS classification, defect width > 10 cm), recurrent ventral hernia, loss of domain (intra-abdominal volume reduction), and complex abdominal wall reconstruction. CT-volumetry and pneumoperitoneum prep may be needed in extreme loss of domain. Mesh reinforcement (synthetic, biologic, or hybrid) is mandatory. Outcomes show recurrence rates of 5-15% in expert centers; surgical site occurrences (seroma, infection) remain a concern. Multidisciplinary approach with optimization of comorbidities is essential.