Question

Match the five terminal branches of the brachial plexus with the upper limb compartments that they innervate. Make sure to note which spinal segmental levels (e.g., C4, C5, etc.) are associated with the various upper limb compartments and the parts of the hand.

Answer 1

The five terminal branches of the brachial plexus with the upper limb compartments that they innervate, which are Axillary, median, musculocutaneous, radial, and ulnar nerves. Upper limb is innervated by the nerves of the brachial plexus.

Axillary Nerves (C5, C6) are terminal Branch of the brachial plexus and traverses by the axilla and posterior to the surgical neck of the humerus. Appears from the posterior cord and innervates both the deltoid and the terse minor muscle. Receives information from the superolateral part of the arm.

Median nerve (C5-T1) - They are terminal Branch of the brachial plexus .Produced from branches of the medial and lateral cords of the brachial plexus. Moves along the midline of the arm and forearm, and profound to the carpal tunnel in the wrist. Innervates most of the anterior forearm muscles, the thenar muscles, and the lateral two lumbricals. Receives sensory information from the palmer side of the lateral fingers and from the dorsal tips if these same fingers.

Musculocutaneous nerves (C5-C7 ) - They are terminal Branch of the brachial plexus and arise from the lateral cord of the brachial plexus. They innervate the anterior arm muscles, which flex the humerus and flex the forearm.

Radial nerves( C5-T1 ) - They are terminal Branch of the brachial plexus and arise from the posterior cord of the brachial plexus. They move along the posterior side of the arm and then along the radial side of the forearm. They innervate the posterior arm muscles and the posterior forearm muscles . Receives sensory information from the posterior arm and forearm surface and the dorso -lateral side of the hand.

Ulnar nerves (C8-T1) - They are terminal Branch of the brachial plexus and arises from the medial cord of the brachial plexus and move downs along the medial side of the arm. It enfolds posterior to the medial epicondyle of the humerus and then moves along the ulnar side of the forearm. They innervate some of the anterior forearm muscles and most of the intrinsic hand muscles, including the hypothenar muscles, the palmar and dorsal interossei, and the medial two lumbricals. Receives sensations from the skin of the dorsal and palmar aspects of the medial little finger and the medial half of the ring finger.