The Subscapular Artery and Its Relationship with the Brachial Plexus

Gil, Young Chun; Yang, Hee Joon; Lee, Hye Yeon

Abstract

The change of arising site of branches from the axillary artery determines it's topographic relationship with the brachial plexus because of closeness between the artery and the plexus. Variation of the subscapular artery (SSA) should be concerned when it is used for the source artery of some flaps, especially focusing on the variation of branching pattern and site of origin and relationships with the brachial plexus. In some cases of absence of SSA, if the circumflex scapular and the thoracodorsal arteries arise from the variable portion of the axillary artery separately, they might change the relationships with the brachial plexus. This study was performed to clarify the relationships between the subscapular artery and the brachial plexus according to the variation of the origin of the SSA and its branch. Two hundred seventeen axillae from 110 Korean cadavers were used for this study. SSA was found in 87.1% of cases, while in 12.9%, the circumflex scapular and the thoracodorsal arteries arose from the axillary artery (AA) seperately. SSA arose most frequently from the third part of the AA (63.6%), and in 4/5 of these cases, it ran behind the radial and ulnar nerves. When it arose from the second part (18.9%) or from the first part (4.6%) of AA, it mostly ran over anterior to the medial cord or/and the ulnar nerve. In 41.9% of the cases, a posterior circumflex humeral artery made a common trunk with the SSA or came from the circumflex scapular artery. In 28.1% of the materials, the SSA made a common trunk with a lateral thoracic artery especially when it arose from the first or second part of AA. After running a mean distance of 2.2 cm from AA, SSA was divided into the circumflex scapular and the thoracodorsal arteies. The SSA gave off the branches to the subscapularis in 68.7% of the cases, and the branches to the serratus anterior in 76.0%.