Morphology of Brachialis Muscle: Variations and Clinical Significance.

ABSTRACT

Background: Though rare but variations of brachialis muscle insertion have been reported. Material and Methods: The study was conducted on 115 upper limbs over a period of 4 years. The dissection of arm and forearm was done carefully to preserve all minute details ,observing the morphology of insertion pattern and nerve supply. Observation Out of 115 specimens, 2 specimens showed insertion of brachialis into bicipital aponeuroses. Accessory slips were seen in 4 specimens which are mixed with main fibers at insertion point. Rarest of all was insertion of an accessory brachialis muscle on radial tuberosity in 2 specimens. The muscle originated from lateral border of shaft of humerus and shared a few fibers with main Brachialis muscle. The muscle was inserted into radius just below the radial tuberosity. Conclusion: The identification of an inter-nervous plane may allow for improvement in the current anterior and anterolateral surgical approaches to the humerus. This could be one of a possible etiology of Radial tunnel syndrome.