Neck Anatomy

Description

Anterior triangle of the neck

Hyoid bone

Lateral view of the cervical spine

Regions of the pharynx

Suboccpital muscle group

Illustration of the anterior, middle and posterior scalen

Nerves of the Posterior Head and Neck Region

Illustration of the cervical plexus

Cutaneous innervation of the head and neck

Arteries in the head and neck

veins and nerves of the neck

Name

• Cervical Spine
• Neck

General

• Neck is defined as the area between the skull base and clavicles
• Transmits the nerves and vessels between the head and trunk

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Areas of the Neck

Anterior Triangle of the Neck

• Borders: inferior border of the mandible, anterior border of Sternocleidomastoid, sagittal plane of mid neck
• Carotid triangle: marks position of bifurcation of the common carotid artery, the internal jugular vein and cranial nerves X & XII
• Muscular triangle: contains Infrahyoid Neck Muscles, pharynx, thyroid gland
• Submandibular triangle: submandibular salivary gland, lymph nodes, facial artery and vein
• Submental triangle: submental lymph nodes

Posterior Triangle of the Neck

• Borders: anterior border of trapezius, posterior border of Sternocleidomastoid, superior border of clavicle
• Inferior belly of omohyoid splits the region into a larger occipital triangle and smaller subclavian triangle
• Occipital triangle: vertebral muscles, prevertebral fascia, Cervical Plexus, Brachial Plexus, Cranial Nerve XI, external jugular
• Subclavian triangle: distal end of subclavian artery

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Bones of the Neck

Hyoid Bone

• U shaped structure located in the anterior neck
• Lies at the base of the mandible at approximately C3
• Attachment for anterior neck muscles

Cervical Spine Anatomy

• The cervical spine is the most superior part of the vertebral column
• Lying between the cranium and thoracic vertebrae
• It consists of 7 distinct vertebrae, two with unique names: Atlas (C1), Axis (C2)

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Viscera of the Neck

• Contains organs for respiratory, endocrine, and gastrointestinal systems

Pharynx

• Connects the nasal and oral cavities to the esophagus and larynx
• Divided into the nasopharynx, oropharynx and laryngopharynx

Larynx

• Proximal component of the respiratory tract
• Based on a cartilaginous scaffold, bound by membranes, ligaments and muscles
• Extrinsic muscles attach to the hyoid bone
• Vocal folds/cords sit inside the larynx protecting the respiratory tract, control phonation, permit coughing

Esophagus

• Muscular tube conducts ingested from laryngopharynx to the stomach
• Muscles are layered in 3 different orientations to permit peristalsis
• Cricopharyngeal muscle forms upper esophageal sphincter

Thyroid Gland

• Found in the anterior neck between C5 and T1, deep to infrahyoid muscles
• Two broad lobes are joined medially by a narrower isthmus

Parathyroid Glands

• Sit in pairs immediately posterior to the thyroid

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Muscles of the Neck

Superficial Neck Muscles

• Platysma
• Sternocleidomastoid

Suboccipital Muscles

• Rectus Capitis Posterior Major
• Rectus Capitis Posterior Minor
• Obliquus Capitis Inferior
• Obliquus Capitis Superior

Deep Neck Flexors Muscles

• Longus Capitis
• Longus Colli
• Rectus Capitis Anterior
• Rectus Capitis Lateralis

Suprahyoid Muscles

• Stylohyoid
• Digastric
• Mylohyoid
• Geniohyoid

Infrahyoid Muscles

• Superficial
  • Omohyoid
  • Sternohyoid
• Deep
  • Sternothyroid
  • Thyrohyoid

Scalene Muscles

• Anterior Scalene
• Middle Scalene
• Posterior Scalene

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Nerves of the Neck

Occipital Nerves

• Greater Occipital Nerve
• Lesser Occipital Nerve
• Third Occipital Nerve
• Suboccipital Nerve

Cervical Plexus

• Network of nerves which form from the anterior rami of C1-C4
• Mixed sensory and motor branches
• Sensory
  • Greater Auricular Nerve
  • Transverse Cervical Nerve
  • Lesser Occipital Nerve
  • Supraclavicular Nerve
• Motor
  • Phrenic Nerve
  • Nerve to Thyrohyoid
  • Ansa Cervicalis

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Blood Vessels and Lymphatics

Common Carotid Artery

• Largest artery of the head and neck
• Branches from the brachiocephalic trunk (right), directly off the Aorta (left)
• At approximately C4, bifurcate into internal and external branches
• External carotid artery supplies the head and neck external to the cranium
• Internal carotid artery is one of two major artery supplies of the cranium

Vertebral Arteries

• Also contribute to intracranial blood supply
• Arise from subclavian arteries, pass through transverse foramen of cervical vertebrae

Internal Jugular vein

• Continuation of the sigmoid sinuses
• Courses inferiorly within carotid sheath, collecting tributaries of the head and neck
• Merges with the subclavian vein at the base of the neck to form the brachiocephalic vein

External Jugular Vein

• Drains the external face
• Merges into the subclavian and anterior jugular veins

Lymphatics

• Superficial lymph nodes loosely form a ring around the head and neck
• They drain into the jugular lymphatic trunks, ultimately into subclavian vein
• Waldeyer's Ring: lymph tissue in the superior pharynx defending against inhaled/ingested pathogens

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Clinical Significance

• See: Neck Pain Main

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See Also

• Neck Pain Main
• Physical Exam Neck
• Anatomy Main

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