Absence of Musculocutaneous Nerve Associated with Variations of Distribution Patterns of the Median Nerve Ausencia del Nervio Musculocutáneo Asociada con Variaciones de los Patrones de Distribución del Nervio Mediano

& Peng XieZHANG, Y.; YANG, S.; YANG, F. & XIE, P. Absence of musculocutaneous nerve associated with variations of distribution patterns ofthe median nerve. Int. J. Morphol., 32(2):461-463, 2014.SUMMARY: Variations in the brachial plexus and the distribution patterns of its branches are not uncommon. A communicatingbranch, which is the most frequent variation, often arises from musculocutaneous nerve to median nerve. However, the branches a risingfrom lateral cord of the brachial plexus and median nerve instead of musculocutaneous nerve are very rare. Detailed description of theabnormalities is important for surgical procedures. Our case study reports the musculocutaneous nerve was absent, a branch from themedial cord innervated the coracobrachialis muscle and two branches from the median nerve innervated the biceps and brachialismuscles, respectively. Moreover, the median nerve gave off the lateral antebrachial cutaneous nerve. This report provides evidence ofsuch possible anatomical variations to surgeons, anesthetists and neurologists during clinical practice.KEY WORDS: Brachial plexus; Musculocutaneous nerve; Median nerve; Absence.