The Cervical Plexus


	Head and Neck

	Vagus (X)

	Spinal Accessory Nerve (XI)

	Cervical Plexus (C2-4)

	Brachial Plexus (C5-T1)

	Upper Extremity

	Musculocutaneous

	Radial

	Median

	Ulnar

	Lower Extremity

	Ilioinguinal / Iliohypogastric

	Femoral

	Sciatic

	Common Peroneal

	Tibial

	Sural

The nerves of the superficial cervical plexus provide sensory innervation to the ear, neck and clavicle. All the nerves of the superficial cervical plexus emerge along the lateral border of the sternocleidomastoid muscle. The cervical plexus can be identified using the interscalene groove as a guide. To do so, slide the ultrasound probe cephalad with the brachial plexus viewed in short axis.

The greater auricular nerve (GAN) from the superficial cervical plexus lies on the sternocleidomastoid muscle just posterior to the external jugular vein. The spinal accessory nerve has a similar course but lies deep to the sternocleidomastoid muscle.

(Roll cursor over image to see labels.)

References

Sheppard DG, Iyer RB, Fenstermacher MJ. Brachial plexus: demonstration at US. Radiology. 1998 Aug;208(2):402-6. PMID: 9680567

Yang WT, Chui PT, Metreweli C. Anatomy of the normal brachial plexus revealed by sonography and the role of sonographic guidance in anesthesia of the brachial plexus. AJR Am J Roentgenol. 1998 Dec;171(6):1631-6. PMID: 9843302

Martinoli C, Bianchi S, Santacroce E, Pugliese F, Graif M, Derchi LE. Brachial plexus sonography: a technique for assessing the root level. AJR Am J Roentgenol. 2002 Sep;179(3):699-702. PMID: 12185049

Demondion X, Herbinet P, Boutry N, Fontaine C, Francke JP, Cotten A. Sonographic mapping of the normal brachial plexus. AJNR Am J Neuroradiol. 2003 Aug;24(7):1303-9. PMID: 12917117

Eichenberger U, Greher M, Kapral S, Marhofer P, Wiest R, Remonda L, Bogduk N, Curatolo M. Sonographic visualization and ultrasound-guided block of the third occipital nerve: prospective for a new method to diagnose C2-C3 zygapophysial joint pain. Anesthesiology. 2006 Feb;104(2):303-8. PMID: 16436850