Open Posterior Component Separation: Transversus Abdominis Release (PCS-TAR) for Ventral Hernia

Abstract

Component separation techniques for complex ventral hernia repair, popularized by Ramirez and colleagues in the 1990s, were developed to mobilize myofascial elements in abdominal wall reconstruction. By division of one of the muscles of the lateral abdominal wall, a low-tension midline closure of large ventral hernia defects can be achieved. Reapproximation of the rectus abdominis muscles in the midline optimizes abdominal wall function and enhances patient quality-of-life. The original Ramirez component separation divides the medial posterior rectus sheath bilaterally, followed by elevation of the rectus abdominis muscles off of the underlying posterior rectus sheaths. If further mobilization of abdominal wall elements is needed, an anterior release divides the external oblique muscle lateral to the linea semilunaris. As abdominal wall reconstruction techniques evolved to include transversus abdominis release (TAR), a distinction between anterior and posterior component separation was needed to indicate which lateral abdominal wall muscle is divided. The posterior component separation (PCS) begins with the standard retrorectus dissection described by Rives and Stoppa and is extended laterally after the posterior lamella of the internal oblique aponeurosis and the transversus abdominis muscle are divided. After the release of the transversus abdominis muscle, the preperitoneal space is entered. Essentially a wide preperitoneal dissection, PCS-TAR offers several advantages over anterior component separation for abdominal wall reconstruction. Large myofascial flaps are mobilized and reapproximated at the midline under minimal tension, creating ample retromuscular space for mesh deployment. This well-vascularized space, isolated from the viscera and superficial wound, encourages early mesh ingrowth and is ideal for inexpensive, bare polypropylene mesh. Additionally, PCS-TAR avoids large skin flaps—and the associated morbidity—needed for an anterior component separation.