**Abstract**

Several surgical methods are performed for the reconstruction of abdominal wall defects after abdominoperineal resection, involving re-suture and free skin grafting. In the complex surgical cases with large abdominal wall defects, the treatment of intestinal fistula and wound infection is challenging. In many cases, they also have had the problems of the control and reposition of a stoma, which has been already present due to the previous unsuccessful surgical procedures. Especially, the case of larger abdominal wall defects with intestinal fistulation, which drains digestive juice into the wound, requires repairing the abdominal wall while fashioning a stoma. This is because a ruptured digestive tract causes infection and inflammation that results in adhesion of the digestive tract, which limits the mobility of both the abdominal wall and bowel. The only method to solve this complex problem is abdominal wall reconstruction with a large vascularized flap and creation of a new stoma on it to separate the wound from drained digestive juice. We present several cases of a large abdominal wall defect, which was reconstructed successfully. Especially, surgical methods using free and perforator flaps are highlighted. These are optimal methods to reconstruct severe abdominal wall defects that involve complications.

**Keywords:** stoma, flap, abdominal wall defect, digestive tract rupture, surgical site infection

### **1. Introduction**

Intestinal stomas are surgically created openings of either the small or large bowel into the anterior abdominal wall. They are often necessary to prevent devastating complications or save a patient's life [1]. Permanent stomas are required when altered anatomy prohibits the re-establishment of gastrointestinal continuity or the risks of undergoing another surgery are prohibitive due to the patient's poor condition. A well-made stoma will have the largest impact on the patient's long-term quality of life.

The principles of stoma creation are typically the same: the opening is created in the abdominal wall, a segment of the bowel is delivered through the external and internal oblique and transversus muscles, and the bowel is opened and secured to the skin [1]. Thus, successful stoma creation requires a healthy abdominal wall and a well-vascularized, tension-free segment of bowel [1, 2].

However, patients who have undergone prior abdominal surgery and developed bowel inflammation and adhesion present with problems, if they require emergent ileostomy for infection or fistulization. Especially, when an

abdominal surgical site infection associated with abdominal wall defect develops, fashioning an intestinal stoma is very challenging [3, 4].

In these cases, reconstruction of a wall defect after abdominoperineal resection is very demanding with regard to the functional outcome. Several surgical methods have been performed involving re-suture, free skin grafting, and local flaps, which can be useful when the defect is relatively small [4]. However, larger abdominal wall defects usually require large flaps [5–7]. If the bilateral abdominal skin was not damaged by previous surgical procedures, abdominal defect may be reconstructed using a large pedicled flap. On the other hand, in the case of larger defects with further complications, such as an antecedent formation of a colostomy or iliac conduit, the free flap transfer is required, because local flaps around the wound cannot be harvested due to the damages of the abdominal skin.

The aim of this article is to describe techniques of stoma creation on the flaps in cases of postoperative fascial necrosis with internal bowel fistulae causing continuous peritoneal contamination. Especially, surgical methods for the two major types of the complications: abdominal wall defect with wound infection "with and without previous stoma" using free and perforator flaps are especially highlighted.
