The presence of anatomical variations of the peripheral nervous system often accounts for unexpected clinical signs and symptoms. We report unusual variations of the lateral and posterior cords of the brachial plexus in a female cadaver. Such variations are attributed to a faulty union of divisions of the brachial plexus during the embryonic period. The median nerve lay medial to the axillary artery (AA) on both sides. On the right, the lateral root of the median nerve crossing the AA and the median nerve in relation to the medial side of the AA was likely the result of a faulty development of the seventh intersegmental artery. We discuss these variations and compare them with the findings of other researchers. Knowledge of such rare variations is clinically important, aiding radiologists, anaesthesiologists and surgeons to avoid inadvertent damage to nerves and the AA during blocks and surgical interventions.
We report a unique variation in the origin and branches of both the left and right external carotid artery (ECA) found during the dissection of a human cadaver. Knowledge of the possible anatomical variations of the ECA is especially important in facio-maxillary and neck surgeries. Surgeons need to be aware of the possibility of encountering such variations, as they may lead to difficulties in differentiating between the external and internal carotid arteries, and in identifying the branches and origins. This knowledge is also important for radiologists in the image interpretation of the face and neck regions.