Why there are two rows of deep inferior epigastric artery perforators despite variability in the number of deep inferior epigastric artery trunks: An anatomical and embryological argument.

The deep inferior epigastric artery (DIEA) distributes musculocutaneous perforators in a uniform pattern that comprises "medial row" versus "lateral row" perforators, with these two rows having anatomical and functional differences. This pattern of two perforator rows is distributed from the DIEA regardless of the number of major DIEA trunks, with there variably being one to four major trunks. As such, a single DIEA trunk will still distribute two perforator rows, as will four major DIEA trunks. What remains to be answered is how such an anatomical fact may come to be? The answer probably lies in the anatomy and embryology of the rectus abdominis muscle itself. With two muscle heads to each hemiabdominal rectus abdominis muscle present from early in its development, it is highly likely that each head of rectus abdominis muscle draws its own blood supply from its source DIEA pedicle, one "perforator row" for each head, regardless of DIEA branching pattern from which these rows are drawn, thus providing an embryological and anatomical basis for the observation of two uniform perforator rows.