A novel internal abdominal oblique muscle flap to close a major abdominal wall defect

This report describes a novel technique for abdominal wall reconstruction using an internal abdominal oblique muscle flap in an Australian kelpie. En bloc resection of a chondrosarcoma and biopsy scar centred on the 13th rib was performed to include full thickness thoracic wall (12th rib, extending caudally) and lateral abdominal wall (including the vascular pedicle of the external abdominal oblique muscle). The diaphragm was advanced to close the thorax. A flap using the caudal internal abdominal oblique muscle with the base dorsally was elevated and rotated 90° to fill the dorsal defect. The ventral defect was closed using the composite ventral abdominal muscles. The skin was closed primarily. The dog developed a self-resolving seroma. Twelve months postoperatively, the dog was able to engage in agility competitions. A viable muscle flap using the internal abdominal oblique muscle provides a useful alternative to previously described techniques for autogenous closure of a large abdominal wall wound.