Neck & Suboccipital Region Learning Objectives

What are the deep cervical fascias?

Investing Fascia, Pretracheal Fascia, Prevertebral Fascia, Carotid Sheath

Describe Investing Fascia

Contents - Sternocleidomastoid and Trapezius muscles, encircles the neck

Platysma muscle found anterior to fascia

Describe Pretracheal Fascia

Surrounds Thyroid cartilage, trachea, and esophagus

Describe Prevertebral Facias

Surrounds body of vertebrae

Describe carotid sheath

Surrounds internal jugular vein (lateral), common carotid artery (medial), CN X - Vagus Nerve (posterior)

Ansa cervicalis directly anterior to carotid sheath

What are the four suprahyoid muscles

Digastric (anterior and posterior bellies), Mylohyoid, Geniohyoid, Stylohyoid

Innervation of Digastric

Anterior Belly - CN V3 Trigeminal Nerve

Posterior Belly - CN XII Facial Nerve

Innervation of Mylohyoid

CN V3 - Trigeminal Nerve

Innervation of Geniohyoid

C1 via XII (Hypoglossal)

Innervation of Stylohyoid

CN XII Facial Nerve

What are the four infrahyoid muscles

Omohyoid (superior and inferior bellies), Sternohyoid, Sternothyroid, Thyrohyoid

Innervation of Omohyoid

Superior belly - Superior root of Ansa cervicalis C1

Inferior belly - Inferior root of Ansa cervicalis C2-C3

Innervation of sternohyoid

Inferior root of ansa cervicalis C2-C3

Innervation of sternothyroid

Inferior root of ansa cervicalis C2-C3

Innervation of thyrohyoid

C1 via XII (hypoglossal)

What are the anterior triangles of the neck?

Carotid Triangle, Muscular Triangle, Submental Triangle, Submandibular Triangle

Describe Carotid Triangle

Boundaries - Anterior SCM, Superior belly of Omohyoid, Posterior belly of Digastric

Contents - Common Carotid Artery

Describe Muscular Trinagle

Boundaries: Anterior SCM, Midline of Neck, Superior belly of Omohyoid

Describe Submandibular Triangle

Boundaries: Mandible, Posterior belly of digastric, Anterior Belly of Digastric

Contents: Submandibular lymph nodes

Describe submental triangle

Boundaries: Anterior belly of Digastric, Midline of Neck, Hyoid Bone

Contents: Submental lymph nodes

What are the posterior triangles of the neck

Occipital triangle, Supraclavicular triangle

Describe Occipital trinagle

Boundaries: Posterior SCM, Inferior belly of Omohyoid, Anterior border of Trapezius

Contents: Cranial Nerve XI - Accessory Nerve, Trunks of Brachual Plexus

Describe supraclavicular triangle

Boundaries: Posterior SCM, Inferior belly of Omohyoid, Clavicle

Contents: Subclavian artery, Thyrocervical trunk (and it’s 4 branches: Suprascapular artery, Transverse Cervical Artery, Inferior Thyroid Artery, Ascending Cervical Artery)

Cervical Plexus

Draw it

Greater Occipital Nerve

Dorsal rami off C2, cutaneous sensory

Lesser Occipital Nerve

Ventral Rami off C2, cutaneous sensory

3rd Occipital Nerve

Dorsal Rami off C3, cutaneous sensory

Great Auricular Nerve

Ventral Rami off C2-C3, cutaneous sensoruS

Supraclavicular Nerve

Ventral Rami off C3-C4, cutaneous sensory

Transverse Cervical Nerve

Ventral Rami off C2-C3, Cutaneous Sensory

Suboccipital Nerve

Dorsal Rami off C1, motor + sensory

C1 via 12

Ventral Rami off C1, motor + sensory, innervates geniohyoid and thyrohyoid

Superior Root of Ansa Cervicalis

Ventral rami off C1, motor + Sensory, innervates superior omoyhyoid

Inferior root of ansa cervicalis

Ventral rami off C2-C3, motor + sensory, innervates inferior belly of omohyoid, sternothyroid, sternohyoid

Phrenic Nerve

Ventral Rami off C3-C5, motor + sensory, innervates diaphragm

Describe 1st Branchial (pharyngeal) arch

Named Mandibular arch; Muscles: Mastication, Mylohyoid, Anterior belly of digastric; Innervated by CN V3 Trigeminal Nerve

Describe 2nd Branchial (pharyngeal) arch

Named Hyoid Arch: Muscles: Facial, Stylohyoid, Posterior belly of digastric; Innervated by CN XII Facial Nerve

Describe 3rd Branchial (pharyngeal) arch

Named 3rd arch; Muscles: Stylopharyngeus; Innervation: CN IX Glossopharyngeal Nerve

Describe 4th Branchial (pharyngeal) arch

Named 4th arch; Muscles: Cricothyroid, Inferior Pharyngeal Constrictor; Innervation: CN X Vagus Nerve (superior laryngeal)

Describe 5th Branchial (pharyngeal) arch

Named 6th arch; Muscles: Intrinsic Laryngeal; Innervation: CN X - Vagus (Recurrent Laryngeal)

Define branchial motor axon function

Innervation of skeletal muscles that are derived from pharyngeal arches

What are the four suboccipital muscles

Rectus Capitis Posterior Major

Rectus Capitis Posterior Minor

Inferior Oblique

Superior Oblique

Rectus Capitis Posterior Major

Action: Extension + Ipsilateral rotation of Neck

Innervation: Suboccipital Nerve C1

Rectus Capitis Posterior Minor

Action: Extension of Neck

Innervation: Suboccipital Nerve C1

Inferior Oblique

Action: Ipsilateral Rotation of Neck

Innervation: Suboccipital Nerve C1

Superior Oblique

Action: Extension of Neck, Lateral Flexion of Neck

Innervation: Suboccipital Nerve C1