Arterial distribution of rectus abdominis masculocutaneous flap and its significance in breast reconstruction

Objective To study arterial distribution of rectus abdominis musculocutaneous flap and to evaluate whether it can be divided into several units for reconstruction. Methods The arteries of the rectus abdominis musculocutaneous flap were studied on 60 sides of cadavers by dissection and angiography. Results The superior epigastric artery (SEA) and the inferior epigastric artery (IEA) continued in a longitudinal direction. Most of their branches took on a typical spiral configuration and communicated with each other within muscle above the level of umbilicus. Many perforating arteries penetrated through the anterior rectus sheath to get to the overlying skin, but the highest concentration of major perforators were in the paraumbilical area. The inferior epigastric artery was more significant than superior epigastric artery in supplying the skin of the musculocutaneous flap. Based on thefstudies of the vascular anatomy of muscles, we could classify arterial distribution into 3 types: type Ⅰ (SEA 26.5 %, IEA 34.6%) revealed a single main intramuscular artery: type Ⅱ (SEA 64.7 %, IEA 48.1%) had two major intramuscular branches; type Ⅲ (SEA 8.8%, IEA 17.3 %) revealed three intramuscular branches. Our anatomic studies showed that the superior and inferior epigastric artery bifurcated or divided into more than two main branches in the majority of cases (SEA 73.5%, IEA 65.4%). Conclusion The rectus abdominis musculocutaneous flap could often be divided into several regions for breast construction which is based on the distribution of each branch of the artery. Key words: Rectus abdominis musclocutaneous flap;  Arterial distribution, Breast reconstruction