The Cervical PlexusThe Cervical Plexus

The cervical plexus is a network of nerves The cervical plexus is a network of nerves formed by communications between the formed by communications between the anterior rami of the upper 4 cervical anterior rami of the upper 4 cervical nerves.nerves.

It lies posterior to the internal jugular vein It lies posterior to the internal jugular vein and the SCM muscles.and the SCM muscles.

The Spinal NerveThe Spinal Nerve

Branches of the Branches of the Cervical PlexusCervical Plexus

Branches of the Branches of the Cervical PlexusCervical Plexus

A. Superficial or Cutaneous BranchesA. Superficial or Cutaneous Branches

Deep branches or muscular and Deep branches or muscular and communicating branchescommunicating branches

A. Superficial or A. Superficial or Cutaneous BranchesCutaneous Branches

1. 1. Ascending branchesAscending branches a. Lesser occipital nervea. Lesser occipital nerveb. Great auricular nerveb. Great auricular nervec. Nervus cutaneous collic. Nervus cutaneous colli

2. 2. Descending branchesDescending branchesa. Medial supraclaviculara. Medial supraclavicularb. Intermediate supraclavicularb. Intermediate supraclavicularc. Lateral supraclavicularc. Lateral supraclavicular

1. 1. Ascending branchesAscending branches

a. Lesser a. Lesser occipital occipital nervenerve

b.b. Great Great auricular auricular nervenerve

c. Transverse c. Transverse cervical nervecervical nerve

a. Lesser occipital nervea. Lesser occipital nerve

- Comes from the second - Comes from the second cervical ventral ramus and cervical ventral ramus and sometimes also from the thirdsometimes also from the third

- supplies the skin on the - supplies the skin on the upper third of the medial upper third of the medial auricular aspect auricular aspect

-connects with the posterior -connects with the posterior branch of the great auricular branch of the great auricular nerve. nerve.

b. The Great Auricular Nerveb. The Great Auricular Nerve

This is the largest ascending This is the largest ascending branch. branch.

It arises from the second and It arises from the second and third cervical rami, encircles third cervical rami, encircles the posterior border of the the posterior border of the sternocleidomastoidsternocleidomastoid

supplies the skin over the supplies the skin over the mastoid process and on the mastoid process and on the back of the auricle, the lobule back of the auricle, the lobule and concha. and concha.

c. Transverse Cutaneous Nerve c. Transverse Cutaneous Nerve

This arises from the second This arises from the second and third cervical rami, curves and third cervical rami, curves round the posterior border of round the posterior border of the sternocleidomastoid the sternocleidomastoid

distributed to the skin of the distributed to the skin of the upper anterior areas of the upper anterior areas of the neck and anterolaterally to the neck and anterolaterally to the skin of the neck, as low as the skin of the neck, as low as the sternum.sternum.

2. Descending branches2. Descending branches

a. Medial a. Medial supraclavicularsupraclavicular

b. Intermediate b. Intermediate supraclavicularsupraclavicular

c. Lateral c. Lateral supraclavicularsupraclavicular

Supra Clavicular NervesSupra Clavicular Nerves These arise by a common trunk from the third and fourth cervical These arise by a common trunk from the third and fourth cervical

ventral rami and emerge from the posterior border of the ventral rami and emerge from the posterior border of the sternocleidomastoid, to descend under the platysma and the deep sternocleidomastoid, to descend under the platysma and the deep cervical fascia;cervical fascia;

3 branches:3 branches:1. The medial supraclavicular nerves supply the skin as far as the 1. The medial supraclavicular nerves supply the skin as far as the

midline and as low as the second rib. They supply the midline and as low as the second rib. They supply the sternoclavicular joint. sternoclavicular joint.

2. The intermediate supraclavicular nerves cross the clavicle to supply 2. The intermediate supraclavicular nerves cross the clavicle to supply the skin over the pectoralis major and deltoid down to the level of the skin over the pectoralis major and deltoid down to the level of the second ribthe second rib

3. The lateral supraclavicular nerves supply the skin of the upper and 3. The lateral supraclavicular nerves supply the skin of the upper and posterior parts of the shoulder. posterior parts of the shoulder.

Deep branches or Deep branches or muscular and muscular and

communicating communicating branchesbranches

11. Lateral branches:. Lateral branches:

a.a. Muscular branches Muscular branches going to the going to the following:following:

i. SCMi. SCM ii. Trapeziusii. Trapezius iii. Levator scapulaiii. Levator scapula iv. Scalenius mediusiv. Scalenius medius v. Scalenius posteriorv. Scalenius posterior

b. Communicating b. Communicating branches to spinal branches to spinal accessory nervesaccessory nerves

Deep Branches—Lateral SeriesDeep Branches—Lateral Series

Muscular branchesMuscular branches

SternocleidomastoidSternocleidomastoid C2, 3, 4C2, 3, 4

TrapeziusTrapezius C2, (3)C2, (3)

Levator scapulaeLevator scapulae C3, 4C3, 4

Scalenus mediusScalenus medius C3, 4C3, 4

Communicating branchesCommunicating branches

AccessoryAccessory NerveNerve C2, 3, 4C2, 3, 4

2. Medial branches:2. Medial branches:

a. Muscular branches going to the following muscles:a. Muscular branches going to the following muscles: i. Prevertebral musclesi. Prevertebral muscles ii. Infrahyoid muscles thru the ansa hypoglossiii. Infrahyoid muscles thru the ansa hypoglossi iii. Diaphragm thru the phrenic nerveiii. Diaphragm thru the phrenic nerve

b. Communicating branches to the vagus, hypoglossal b. Communicating branches to the vagus, hypoglossal and sympathetic nervesand sympathetic nerves

c. Phrenic nerve is the most important branch because it c. Phrenic nerve is the most important branch because it supplies the diaphragm which is the chief muscle for respiration. supplies the diaphragm which is the chief muscle for respiration. It is derived from cervical nerves 3, 4, and 5.It is derived from cervical nerves 3, 4, and 5.

Communicating and Muscular Communicating and Muscular BranchesBranches

(Medial Series)(Medial Series)Communicating branches withCommunicating branches with

HypoglossalHypoglossal C1, 2C1, 2VagusVagus C1–4C1–4SympatheticSympathetic C1, 2C1, 2

Muscular branches toMuscular branches toRectus capitis lateralisRectus capitis lateralis C1C1Rectus capitis anteriorRectus capitis anterior C1, 2C1, 2Longus capitisLongus capitis C1–3C1–3Longus colliLongus colli C2–4C2–4Inferior root of ansa cervicalis Inferior root of ansa cervicalis C2, 3C2, 3

Phrenic nervePhrenic nerve C3–5C3–5

The Ansa HypoglossiThe Ansa Hypoglossi Formed by spinal nerves C1, C2, and C3.Formed by spinal nerves C1, C2, and C3.

3 parts:3 parts:1. Superior root1. Superior root C1C1

- innervates the superior belly of - innervates the superior belly of omohyoidomohyoid

2. Inferior root2. Inferior root C2, C3C2, C3

3. Loop of ansa cervicalis3. Loop of ansa cervicalis- innervates the sternothyroid, - innervates the sternothyroid, sternohyoid, inferior belly of omohyoidsternohyoid, inferior belly of omohyoid

The Phrenic nerveThe Phrenic nerve

Arises from the converging APR of spinal Arises from the converging APR of spinal nerves C3, C4, and C5.nerves C3, C4, and C5.

This is the sole motor supply to the This is the sole motor supply to the diaphragm, and also contains widespread diaphragm, and also contains widespread sensory fibres. sensory fibres.

Give your loved ones the Give your loved ones the warmest hugs and kisses warmest hugs and kisses

you can give today!!you can give today!!