A new extended external oblique musculocutaneous flap for reconstruction of large chest-wall defects

A new extended external oblique musculocutaneous flap utilized in the reconstruction of chest-wall defects is described. The flap is drawn as a V-Y rotation flap on the ipsilateral abdominal wall. It is laterally based, and its pedicle coincides with the five lowest costal insertions of the external oblique. The flap extends above the transiliac line, from the posterior axillary line to the linea alba, and includes the dynamic territory of the external oblique muscle. Vascular supply is provided by the musculocutaneous perforating arteries of the intercostal vessels and their subcutaneous branches. The flap is raised medially and includes the anterior sheath of the rectus. Undermining continues between the external and the internal oblique muscles as far as the posterior axillary line. The donor site on the abdominal wall is reinforced by the plication of the internal oblique sheath. This flap was used in 13 patients with major anterior chest-wall excisional defects. The mean chest-wall defect was about 390 cm2. Marginal necrosis with distal skin loss was observed in one patient. All other flaps healed without complications. The extended external oblique musculocutaneous flap differs from other external oblique flaps already described in several aspects that allow it to obtain better functional and aesthetic results.