Lecture Notes on the Brachial and Lumbar Plexuses

Flashcards covering the key nerves and structures of the brachial and lumbar plexuses.

Brachial Plexus

Formed from the anterior rami of C5-T1; supplies motor and sensory innervation to the upper limb.

Superior Trunk

C5 and C6 unite to form this structure.

Middle Trunk

Formed by C7.

Inferior Trunk

C8 and T1 unite to form this structure.

Axillary Nerve

Branch of the posterior cord; serves structures near the axilla, including the deltoid and teres minor muscles.

Musculocutaneous Nerve

Distal continuation of the lateral cord; serves the anterior arm muscles that flex the forearm and the skin of the lateral forearm.

Radial Nerve

Distal continuation of the posterior cord; serves the muscles that extend the forearm and hand as well as the skin in the lateral hand.

Ulnar Nerve

Distal continuation of the medial cord; supplies certain muscles in the forearm that flex the hand, most of the intrinsic muscles of the hand, and the skin over the medial hand.

Median Nerve

Results from the fusion of portions of the medial and lateral cords; supplies most of the muscles of the forearm that flex the hand, certain intrinsic hand muscles, and the skin over the anterior and lateral hand.

Lumbar Plexus

Formed from the anterior rami of L1-L4 with a small contribution from T12; supplies motor and sensory innervation to the lower limb and pelvic region.

Iliohypogastric and Ilioinguinal Nerves

Supply motor innervation to the transversus abdominis and internal oblique muscles and sensory to the pelvic area.