30 - Aberrant Communicating Branches of the Brachial Plexus

Poster Board Number: 30
There are separate poster presentation times for odd and even posters.
Odd poster #s – first hour
Even poster #s – second hour

Abstract Body : Introduction and Objective: The brachial plexus is a major collection of nerves originating from the spinal cord that extends to the bilateral shoulder, arms, and hands to transmit sensory and motor signals. Knowledge of brachial plexus anatomy is critical for diagnosing and managing related injuries. Our case highlights a bilateral variation found in the brachial plexus.

Materials and Methods: A variation in the brachial plexus was found during the anatomy lab dissection of a 76 year old Caucasian female. Blunt dissection was performed to isolate and preserve the brachial plexus and the surrounding structures. Meticulous dissection of the variation and its respected structures was performed and are pictured with graphical edits to illustrate our findings.

Results: We observed a communicating branch between the Lateral cord and Ulnar nerve during routine anatomy lab dissection of the upper limb and brachial plexus. In addition to the contributions from the Median cord, the Ulnar nerve also received contributions via a communicating branch from the Lateral cord. The communicating branch was present bilaterally, while the remainder of the brachial plexus and upper limb musculature remained unremarkable.

Conclusion: The typical ulnar nerve is supplied by spinal roots C8 and T1 and innervates the flexor carpi ulnaris, the medial half of the flexor digitorum profundus, and most intrinsic hand muscles (1). It also supplies the skin in the medial aspect of the hand. In our dissection, we found a variation in this anatomy where the Lateral cord and Ulnar nerve have a communicating branch bilaterally.

Significance/Implication: During a physical examination and surgical procedure involving the axilla and its distal region, physicians can use knowledge of the brachial plexus to avoid damaging the structure and orient themselves. Additionally, an understanding of this variation will allow physicians to create more effective treatment plans when it comes to potential nerve pathologies.

Citations:
Johnson EO, Vekris M, Demesticha T, Soucacos PN. Neuroanatomy of the brachial plexus: normal and variant anatomy of its formation. Surgical & Radiological Anatomy 2010; 32: 291-297. https://doi.org/10.1007/s00276-010-0646-0