Variations in brachial plexus and the relationship of median nerve with the axillary artery: a case report

Abstract

BackgroundBrachial Plexus innervates the upper limb. As it is the point of formation of many nerves, variations are common. Knowledge of these is important to anatomists, radiologists, anesthesiologists and surgeons. The presence of anatomical variations of the peripheral nervous system is often used to explain unexpected clinical signs and symptoms.Case PresentationOn routine dissection of an embalmed 57 year old male cadaver, variations were found in the formation of divisions and cords of the Brachial Plexus of the right side. Some previously unreported findings observed were; direct branches to the muscles Pectoralis Minor and Latissimus dorsi from C6, innervation of deltoid by C6 and C7 roots and the origin of lateral pectoral nerve from the posterior division of upper trunk. The median nerve was present lateral to axillary artery. The left side brachial plexus was also inspected and found to have normal anatomy.ConclusionThe probable cause for such variations and their embryological basis is discussed in the paper. It is also concluded that although these variations may not have affected the functioning of upper limb in this individual, knowledge of such variations is essential in evaluation of unexplained sensory and motor loss after trauma and surgical interventions to the upper limb.

Origin of Medial and Lateral Pectoral Nerves from the Supraclavicular Part of Brachial Plexus and its Clinical Importance – A Case Report

“…The lateral pectoral nerve may arise from the lateral cord or from the anterior divisions of the upper and middle trunks [9]. Gupta et al, [10] have reported the origin of two lateral pectoral nerves as two separate branches from the anterior divisions of upper and middle trunks.Its origin from the posterior division of the upper trunk has been reported by Singhal et al, [11]. In the same study, they noted the origin of medial pectoral nerve directly from the C6 root.…”

Third Head of Biceps Brachii Muscle, Associated with Musculocutaneous and Median Nerve Bilateral Communication and with a Communicating Branch Between Median Nerve Roots

“…He described the presence of two communicating branches between roots of median nerve. Both ranged from the medial root to the lateral root of the nerve, and likewise in this case, the presence was unilateral with a 2.1% frequency (1 of 48 upper limbs) According Singhal et al (2007) the anomalous communicating branches that crosses the axillary artery by its anterior view, can cause compression syndromes, producing ischemia. According to Badawoud, the presence of this communicating branch could compress the axillary artery and reduce blood supply to the upper limb.…”

Bilateral single cord of the brachial plexus in an adult female cadaver of South Indian origin

“…In the case of a single common cord, the subclavian artery possibly arises from a more distal intersegmental artery rather than the usual seventh cervical intersegmental artery. This would allow for the more proximal fusion of the constituents of the brachial plexus, and accordingly, an artery would no longer intervene between the middle and lower trunk [3, 15]. …”