Variation in the Nerve Supply to Coracobrachialis Muscle - A Case Study

Abstract

Coracobrachialis muscle is a muscle of the adductor compartment of arm. It is supplied by musculocutaneous nerve, a branch from the lateral cord of brachial plexus. The study was done between 2008-2012 [5 years] in J.J.M.M.C. and S.I.M.S. & R.C. The present case was found in a male cadaver aged around 60years. During the routine cadaveric dissection of undergraduate students in J.J.M.M.C Davangere, we found that coracobrachialis muscle was supplied by two accessory nerve twigs which were found to arise from lateral cord of brachial plexus. Musculocutaneous nerve normally supplies the coracobrachialis muscle which is a branch from lateral cord of brachial plexus. In our case it was noted that two accessory nerve twigs were found to arise from lateral cord of brachial plexus supplying coracobrachialis muscle which entered the muscle before the piercing of musculocutaneus nerve. The occurrence of accessory nerve supply to the coracobrachialis is a rare finding and is more of a phylogenetic importance. The knowledge of such type of variation is important for anatomists and surgeons operating in this region.