Bilateral Non-Formation of Upper Trunk of the Brachial Plexus with a Unilateral Communication Between the Musculocutaneous Nerve and the Median Nerve: A Case Report 1637-1640
184, Medical Enclave, Circular Road,
Amritsar - 143001, Punjabb, India.
Variations in the brachial plexus are common and they have been reported in relation to the origin of the roots, trunks, cords, divisions and the branches. They may prove to be valuable to the orthopaedic surgeon, the radiologist, the anaesthesist, the neurosurgeon, the neurologist, and the vascular surgeons while they perform their respective procedures. In this report, a rare, bilateral non-formation of the upper trunk of the brachial plexus with a unilateral communication between the musculocutaneous nerve and the median nerve has been reported. C5 and C6 on both the sides did not join to form the upper trunk. On the right side, it separately divided into the anterior and the posterior divisions. On the left side, C5 did not give any anterior division and continued as the posterior cord after receiving the posterior division of C6. A communicating branch from the musculocutaneous nerve to the median nerve was also seen on the left side. An earlier unilateral non-formation of the brachial plexus has been reported, with an incidence of 1%, but a bilateral variation is extremely rare. Further, its ontogeny and clinical implications have been discussed in detail.