Advancement of the external oblique muscle flap to improve the waistline: a study in cadavers.

Waist definition is an important goal of abdominoplasty. The purpose of this report is to study the effect of advancement and rotation of the external oblique muscles in the waistline. Twenty cadavers were dissected. Two parameters were analyzed: measurement of the waist circumference and the width of overlapped skin flaps of the abdomen in the midline. Three stages of dissection were compared: (1) initial stage, in which the myoaponeurotic structure of the anterior abdominal wall was intact; (2) stage 1, after advancement of the rectus muscles and its anterior aponeurosis toward the midline; and (3) stage 2, after advancement and rotation of the external oblique muscle. A significant statistical difference was found when waist circumference measured before dissection was compared with values obtained after the procedure. When the width of the overlapped skin flaps was compared during the different stages of dissection, a significant statistical difference was observed after each stage (paired t test). Therefore, the approximation of the rectus muscles alone improves the waistline, and when associated with external oblique muscle flap advancement and rotation, the cosmetic result in this area is even better. In conclusion, the procedure described decreases waist circumference and improves the frontal view of the waist.