Anatomical variations on the origin of the dorsal scarular artery: about 58 dissections

Abstract

Introduction: The dorsal scapular artery (Arteria dorsalis scapulae) is often described as the last collateral branch of the subclavian axis. It anastomoses extensively with the transverse artery of the neck (arteria transversa cervicis) to irrigate the trapezius muscle. However, its origin can be very variable. The objective of this work was to study the different modalities of birth of the arteria dorsalis scapulae from the subclavian artery. Material and methods: We performed dissection of 58 supraclavicular regions from 32 bodies preserved in a non-formalin solution rich in glycerine. The subclavian artery (arteria subclavia) was exposed, as well as all its collateral branches. The arteria dorsalis scapulae was identified by its location as collateral and its route, and then injected with a solution of methylene blue and gelatin. Results: Our results were divided into 3 types according to the mode of birth and the branch of origin. In 21 cases, the arteria dorsalis scapulae and the arteria transversa cervicis were born from a common trunk stemming from the arteria subclavia (type I). In 27 cases, the arteria dorsalis scapulae was born directly from the arteria subclavia, while the arteria transversa cervicis came from the thyro-cervical trunk or truncus thyrocervicalis (type II). In 10 cases, the dorsalis scapulae and transversa cervicis arteries all represented collateral branches of the thyro-cervical trunk (type III). Conclusion: The formation of the arteria dorsalis scapulae from the subclavian axis can present numerous anatomical variations. These variations must be taken into account during the surgery of flaps of the trapezius muscle.