Alternative vascular pedicle of the anterolateral thigh flap: does an oblique branch really exist?

Alternative Vascular Pedicle of the Anterolateral Thigh Flap: Does an Oblique Branch Really Exist? Sir: W read with interest the article by Wong et al.1 and the recently published letter to the editor by da Costa and Lancelotti2 concerning the oblique branch of the lateral circumflex femoral artery. Wong et al. described a distinct vascular pedicle lateral to the descending branch of the lateral circumflex femoral artery (which was present in 35 percent of their clinical cases) and stated that this vessel was as yet unnamed. A claim to have identified a completely new branch in the well-known vascular system of the lateral circumflex femoral artery should, however, be made with caution. It implies of course a thorough understanding of the valid international terminology and the anatomical literature. Moreover, this finding should be based on an anatomical study with a representative number of specimens. According to the description of Wong et al. and the diagram in Figure 1, the lateral circumflex femoral artery splits into two main branches, a transverse and a descending one. The branches between these main branches are designated as the new “oblique branch.” This is in contrast to international anatomical terminology3 and the German and English literature, which do not list an oblique branch of the lateral circumflex femoral artery.4,5 This, of course, would not exclude the existence of such a branch. However, following the “classic” descriptions, the lateral circumflex femoral artery splits into three branches, the ascending, the transverse, and the descending branches. According to the description of Thiel, the ascending branch crosses underneath the rectus femoris muscle to supply the tensor fasciae latae muscle. The transverse branch generally arises from this ascending branch and runs laterally and ventral to the vastus intermedius muscle. Most of its branches enter the vastus lateralis muscle. The descending branch, which may arise from the femoral artery directly, runs distally between the rectus femoris and vastus intermedius muscles. The same description can be found in Gray’s Anatomy5 and in the corresponding author’s recently published book.6,7 By applying these descriptions to the work of Wong et al. and the diagram, the so-called oblique branch could in fact be the transverse branch of the lateral circumflex femoral artery. In contrast, in this study, the “oblique branch” was only present in 35 percent of the cases, which is in contrast to the constant presence of this branch in the anatomical literature. This difference can be explained by the design of the study. It was performed on clinical cases, and the “oblique branch” was only dissected when present during the harvest of an anterolateral thigh flap. It is not clear and not mentioned by the author whether the dissection of the remaining flaps was carried out in all clinical cases to a point where an “oblique branch” could have been detected. This would mean that the remaining 65 percent of the cases were not included in this study—and perhaps more proximally located transverse branches were simply missed. The possibility of harvesting an anterolateral thigh flap based on an alternative pedicle is helpful, and the efficiency of this procedure has been proved by the authors. Nevertheless, the designation of a new branch of a well-described vascular system should be made on the basis of the international anatomical nomenclature and literature, and it should be made on the basis of an anatomical study rather than on clinical cases. DOI: 10.1097/PRS.0b013e3181d51655