The bipedicled and bipartite latissimus dorsi free and perforator flap: an anatomic study.

Abstract

The purpose of this study was to search for an enhanced blood supply in the distal one third of the latissimus dorsi and, thus, to have a closer look at the muscular branches of the intercostal vessels. The muscle branches to the latissimus dorsi muscle arising in the "costal groove" segment of the three lowermost intercostal vessels (ninth to eleventh interspaces) were identified bilaterally in 28 fixed hemithoraces (84 interspaces). In the interspaces, the perforators 0.5 mm or greater were localized and dissected free to their junction with the intercostal source vessels. The number of branches was recorded and external diameters of branches and source vessels were measured. At least one big muscular branch to the latissimus dorsi was found in every hemithorax. In the tenth and eleventh interspaces, at least one branch was found in all cases; in the ninth interspaces, one branch was found in 93 percent of cases. A second big branch was found in approximately half of the ninth and tenth interspaces, and in one fourth of the eleventh interspaces. The external mean diameter of the muscular branches at their branching point from the source vessel was 1.5 mm for the artery and 1.8 mm for the vein. The versatility of the latissimus dorsi muscle can be enhanced by including intercostal vascular branches of the intercostal groove segment into the flap design. The latissimus dorsi can be harvested as a bipedicled free flap; thus, it allows the harvest of two separate bipartite, independent muscle, musculocutaneous, or perforator flaps.