The Brachial Plexus: Variations are The Rule

Anatomical variations of the brachial plexus are so common, it is crucial to look for them before surgical correction of the different injuries of the plexus and prior to supra or infraclavicular plexus block. This study was done to identify the variations of the brachial plexus and highlight their clinical significance. The materials of this study included 20 cadaveric specimens obtained from the Faculty of medicine, University of Alexandria which were dissected to find the variations of the different parts of the plexus. Variations were found in 90% of cases and involved all the stages of the plexus, prefixed pattern was found in 40% of cases, postfixed in 15% and both prefixed and postfixed in 5%. Anomalous formation of the trunks or cords as well as abnormal origin of the branches were detected. Communicating branches existed between the different parts of the plexus. The brachial plexus is very variable, even in the same person the right and left sides may not be similar. Disagreement exists between different studies as regards the location and description of the variations. The anatomical basis of brachial plexus variations should be kept in mind, especially when interpreting clinical symptoms following trauma or tumor events. The presence of variations can affect the decision and type of repair for brachial plexus injury.