The coracoid process is supplied by a direct branch of the 2nd part of the axillary artery permitting use of the coracoid as a vascularised bone flap, and improving it's viability in Latarjet or Bristow procedures

Abstract

A comprehensive understanding of the anatomy of the vascular supply of the coracoid is needed to ensure that the coracoid remains vascularised in order to optimize bone union during any coracoid transfer procedures. It is the purpose of this study to present an anatomical overview of the blood supply of the coracoid process, describing a previously unidentified vessel that arises directly from the axillary artery and nourishes the coracoid process, permitting the coracoid to be used as a free bone flap. An anatomical study examining the blood supply to the coracoid process of the scapula was performed in 14 shoulders from 7 fresh frozen (unembalmed) adult cadavers. In addition, the vascular supply to the coracoid was studied in 22 shoulders in patients during operations around the anterior shoulder. In all the cadaveric shoulders studied there was a single consistent direct branch of the second part of the axillary artery that supplied the distal 2-3cm of the coracoid process with a corresponding vein. The mean pedicle length for the artery was 4.46cm (range 3.1-5.6cm). This artery originated from the axillary artery from the antero-lateral position in 6, lateral position in 3 and posterolateral position in 5 shoulders. The mean pedicle length for the vein was 5.8cm (range 4.5-7.8cm). The vein joined directly to the axillary vein in 3 shoulders and via another tributary (parallel to the axillary vein) in 9 shoulders. The diameter of the artery and vein averaged 1-1.5mm. The clinical study confirmed the findings of the cadaveric study. Our anatomical cadaveric and clinical studies demonstrate the presence of a previously unidentified direct arterial branch from the second part of the axillary artery supplying the anterior 2-3cm of the coracoid process of the scapula. This consistent vessel and accompanying vein should be preserved for any surgical procedure that involves transfer of the coracoid process, such as the Laterjet and Bristow procedures for shoulder dislocation and can be used for free transfer of the coracoid where a small vascularised bone flap may be required.