The 4 Major Nerve Plexuses

Practice flashcards covering the four major nerve plexuses, their locations, key nerves, and functions based on lecture notes.

Cervical Plexus

A nerve plexus that emerges from vertebrae $C3$ through $C5$.

Phrenic nerve

The key nerve of the cervical plexus that innervates the diaphragm muscle, which is essential for breathing.

Brachial Plexus

A nerve plexus that emerges from the lower cervical vertebrae and thoracic vertebra $1$ ($T1$).

Musculocutaneous nerve

A nerve from the brachial plexus that controls the muscle and skin of the arm (brachium).

Radial nerve

A nerve from the brachial plexus that controls muscles along the radius bone.

Ulnar nerve

A nerve from the brachial plexus that controls muscles along the ulna bone; its passageway includes the groove between the olecranon process and medial epicondyle.

Lumbar Plexus

A nerve plexus that emerges from the lower back region.

Femoral nerve

The key nerve of the lumbar plexus that controls the sartorius and quadriceps muscles in the thigh.

Sacral Plexus

A nerve plexus that emerges from the lower back and upper sacral region.

Sciatic nerve

The key nerve of the sacral plexus that controls the hamstring muscles at the back of the thigh.

Thoracic Region Nerves

Nerves branching off the spinal cord in this region that are single branches rather than an interwoven network; there is no thoracic plexus.