The Brachial Plexus: More and More Variations

Abstract

The brachial plexus is so variable that most of dissected cases will show some form of anatomical variations. In the same person, the right and left sides are not the same. This study was done to identify the variations of the brachial plexus and highlight their clinical significance. The materials of this study included 10 cadavers dissected on both sides to find out the variations of the different parts of the plexus. Variations were found in 85% of cases. Variations included all stages of the plexus. Phrenic nerve took origin from the upper trunk in 10%, while the lateral pectoral nerve took origin by 2 roots from the upper and middle trunks or from the lateral and medial cords in 40%. Abnormal communications were found between the trunks, cords, or branches. Abnormal relations were found between the trunks, cords, or branches and the subclavian or axillary arteries. It is essential to know the exact anatomy of the brachial plexus prior to surgical repair of brachial plexus injuries or prior to supra or infraclavicular plexus block. Variations of brachial plexus are so common. Researchers have been trying for so long to assign specific patternsfor brachial plexus. Their efforts were inutile and now is the time to acknowledge anatomical variations of brachial plexus as the rule.