Anatomical review of the brachial plexus

Anatomy is the key of success for all regional anesthesia techniques. Knowledge of the relevant brachial plexus anatomy and its relations, as well as the distribution of its sensory and motor innervation to the upper extremity, is crucial for understanding the resulting distribution of sensory anesthesia and motor blockade. Correct identification of superficial bony, muscular and vascular landmarks and profound structures are fundamental to achieving consistent success and minimizing complications with brachial plexus anesthesia. The different approaches to the plexus determine the characteristics of the resulting anesthesia that only occurs if a high local anesthetic volume is delivered sufficiently near the desired neural structures and into the brachial plexus sheath.