The middle trunk is formed from the root of C7 only.The superior trunk is formed by the roots of C5 and C6.Finally, the brachial plexus gives rise to five main terminal branches that are responsible for the most of motor and sensory innervation of the upper limb, and they include the musculocutaneous, axillary, radial, median and ulnar nerves.Įach trunk has a well-known scheme of origin from the roots of the brachial plexus: The posterior cord of the brachial plexus gives off the upper subscapular nerve, thoracodorsal nerve and lower subscapular nerve. The medial cord gives rise to medial pectoral nerve, medial cutaneous nerve of the arm, and medial cutaneous nerve of the forearm. The lateral cord gives rise to the lateral pectoral nerve. The preterminal infraclavicular branches emerge from the lateral, medial and posterior cords of the brachial plexus. The infraclavicular branches can be further divided into preterminal and terminal branches. The supraclavicular branches include the dorsal scapular nerve, suprascapular nerve, long thoracic nerve and subclavian nerve. With respect to its position to the clavicle, these branches can be divided into supraclavicular and infraclavicular branches. The brachial plexus gives rise to a number of branches that leave the plexus at various points along its length. The six divisions then reform, resulting in three cords: posterior, lateral and medial cords. Each trunk then divides into an anterior and posterior division, therefore forming six divisions altogether. These roots merge to form three trunks: superior (C5-6), middle (C7) and inferior (C8-T1).

The brachial plexus is formed by five anterior rami that originate from the spinal nerves C5-T1 (these are known as the roots of the brachial plexus). (standing for Dropped wrist = Radial nerve lesion, Claw hand = Ulnar nerve lesion, Ape hand = Median nerve lesion) (standing for: Upper subscapular nerve, Lower subscapular nerve, Thoracodorsal nerve, Radial nerve, Axillary nerve) (standing for: Medial cutaneous brachial nerve, Medial cutaneous antebrachial nerve, Medial pectoral nerve, Ulnar nerve, Median root of median nerve) 'Rugby players Make Many Moves Using Muscles' (standing for: Lateral pectoral nerve, Lateral root of median nerve, Musculocutaneous nerve) (standing for: Roots, Trunks, Divisions, Cords, Branches Key facts about the brachial plexus RootsĬomplete sensory and motor innervation of the arm This article will discuss the anatomy and functions of the brachial plexus. For this reason, we’ve prepared a clear and concise overview of the brachial plexus, as well as mnemonics and other learning hacks that will help you understand and memorize the brachial plexus. The brachial plexus can be a very challenging topic to understand due to its complex origin, branching, and relations and students often get lost while reading the textbooks. In addition to terminal branches, the brachial plexus gives rise to several preterminal branches called supraclavicular branches, which leave the plexus at various points along its length. These terminal branches are responsible for motor and sensory innervation of the upper limb, and they include the musculocutaneous, axillary, radial, median and ulnar nerves.

This plexus arises from the anterior rami of spinal nerves C5-T1 that undergo several mergers and splits into trunks and divisions, until they finally give rise to their terminal branches. The brachial plexus is a network of nerves that gives rise to all the motor and sensory nerves of the upper extremity.

Complete anatomy brachial plexus