A rare anatomical variation of the brachial plexus: single cord anomaly.

Anatomical variations of the brachial plexus may be important in regional anesthesia and upper limb procedures. A fused single cord of the brachial plexus, although considered rare, was discovered in 4 Indian male cadavers during the dissection of 90 brachial plexuses. All 4 cases demonstrated deviation from the usual pattern starting at the division of trunks continuing to the formation of cords. The location of these single cords was lateral to the axillary artery instead of the typical perivascular relationship. A fused single cord of brachial plexus might be more common than previously thought. The impact on the performance or success of blockade remains unknown.