The entire prior skin incision is excised along with any underlying fibrosis back to healthy epidermis and subcutaneous fat in attempt to minimize infection (FIG 1A).

Dissection proceeds directly down to the hernia sac, being careful not to enter the sac. If the incision is longer than the hernia defect, only the skin and subcutaneous tissues that are chronically scarred with concerns for healing need be excised. This type of repair can be accomplished totally extraperitoneally. The lateral aspect of the hernia sac is mobilized medially back to the fascial defect. This maneuver may be accomplished purely by blunt dissection, but if the interface of sac and subcutaneous tissue is scarred, sharp dissection may be required (FIG 1B).

The skin and subcutaneous tissue flaps are mobilized for at least 5 to 7 cm lateral to the edge of the hernia defect. This plane is created just anterior to the abdominal wall fascia (anterior rectus fascia and possibly out to the external oblique fascia or aponeurosis more laterally) to allow a wide, lateral overlap of the prosthesis. A 5- to 7-cm skin and subcutaneous flap is mobilized off the midline fascia past the cranial and caudal extents of the hernia defect (FIG 1C).

A decision needs to be made whether and how the fascial edges of the defect can be reapproximated (FIG 2A) or only bridged or “patched” by the prosthesis (FIG 2B) (see Part 2, Chapter 5). If the fascial edges are to be sutured together, some dissection under the fascial edges may be necessary to place the fascial sutures safely. Most surgeons believe that reapproximation of the fascial edges reinforced by a prosthesis provides a superior outcome compared to a bridge or patch of a persistent fascial defect. If the defect is wide and would require a more complicated abdominal wall reconstruction, the advantages and disadvantages should be considered. In this situation, the skin flaps can be dissected further laterally beyond the lateral border of the rectus muscle; then the external oblique fascia and muscle can be transected being careful not to disrupt the internal oblique muscle/fascia—a form of anterior components separation—this maneuver allows the rectus muscle to be “medialized” and the medial edges of the fascia to be sewn together (FIG 2C) (see Part 2, Chapter 5, for more in-depth description). This maneuver allows 4 to 6 cm of medialization of the rectus muscles on both sides. Another option to “approximate” the fascial edges of the defect is a rectus rollover technique (FIG 2C). With this technique, the anterior rectus fascia is incised just medial to its lateral border, mobilized off the underlying rectus muscle, and “rolled” medially. These edges of the rolled anterior rectus fascia can be sutured together in the midline. Note that the rectus muscles are not medialized with this technique.

A large sheet of prosthetic mesh is then sized to cover the anterior abdominal wall hernia defect and to extend a further 5 to 7 cm from the hernia defect (so-called “wide onlay”) on all sides of the defect. The lateral edges of the prosthesis are sewn to the anterior abdominal wall fascia circumferentially with #0 or no. 1 suture material (e.g., 0 or no. 1 polydioxanone) (FIG 3). The use of absorbable versus permanent sutures is controversial. Proponents of permanent sutures believe that permanent sutures minimize the possibility of late migration or dislodgement of the prosthesis, whereas those surgeons favoring the longer lasting absorbable suture (such as polydioxanone) believe that permanent sutures can lead to suture granulomas and ultimately contamination and infection of the prosthesis. Although there is no good evidence supporting either argument, we prefer the absorbable suture provided there will be a large surface area for mesh transgrowth.

In progressively smaller concentric circles, one or two additional suture fixation of the prosthesis to the underlying anterior abdominal wall can also be placed (FIG 3A). If the repair is a bridge repair, these concentric circles should not extend medial to the edges of the fascial defect because the underlying hernia sac and viscera can be injured. A porous synthetic prosthetic and not a solid prosthetic (ePTFE) is used to achieve the goal to provide a
wide surface area for transgrowth through the mesh for tissue fixation.

If an anterior components separation is performed, the prosthesis extends laterally to the lateral transected edge of the external oblique aponeurosis (a very wide onlay repair) or just 5 to 7 cm lateral to the medial edge of the hernia defect which is usually to the lateral edge of the rectus muscle.

If a rectus rollover is performed, the prosthesis should extend 5 cm lateral to the site of incision in the anterior rectus fascia to provide solid points of fascial fixation of the prosthesis.

For situations where there is bacterial contamination (clean-contaminated cases) or active infection, albeit treated, a synthetic mesh is contraindicated, and a bioprosthesis would be a better choice.

Most surgeons place one or two closed suction drains in the large subcutaneous space to prevent a seroma. When the drains should be removed is controversial; for a bioprosthesis, drains are mandatory to prevent a seroma.

Prior to closing the skin, a pleating technique may be used, whereby the posterior adipose surface of the skin/subcutaneous flaps can be sewn to the anterior surface of the prosthesis in attempt to minimize the “dead space” and the possibility of seroma (FIG 3B).

As with other repairs, the incision should be made directly over the hernia defect with resection of the skin incision and the underlying, poorly vascularized scar tissue. The skin incision preferably should not extend all the way up to the xiphoid or all the way down to the pubis but rather stay 5 to 8 cm away from xiphoid and pubis.