Compartments of the Neck Flashcards
The neck is divided up into two major triangles (anterior and posterior), which are separated by the
Sternocleidomastoid muscle
Each triangle contains skeletal elements, muscles, and neurovascular structures. In addition, the anterior triangles contain
Visceral structures (Esophagus and endocrine glands)
The bones of the neck include the
7 Cervical Vertebra and the hyoid bone
Have features common to most vertebra and are characterized by the presence of foramina within their transverse processes for transmittance of the vertebral artery and veins
C3-C6
Whatis unique about the C7 vertebra?
It has a long spinous process
Has superiorly placed facets for articulation with the base of the skull, no vertebral body, and no spinous process
C1 (Atlas)
Has the odontoid process (Dens) fused to its vertebral body
C2 (axis)
Located in the anterior part of theneck at the level of the C3 vertebra in the angle between the mandible and thyroid cartilage
Hyoid Bone
Does the hyoid bone articulate with any other bones?
No
Suspended by muscles that connect it to the skull, thyroid cartilage, sternum, and scapula
Hyoid Bone
The hyoid bone is attached to the thyroid cartilage via the
Thyrohyoid membrane
The hyoid bone plays a role in
Swallowing and phonation
The cartilages of the neck include
-Form the skeleton of the larynx and airway
Thyroid, cricoid, arytenoid, and tracheal
Part of thyroid cartilage that is palpable in the midline of the neck
Laryngeal prominence (Adam’s apple)
What is attached to the hyoid bone:
- ) Superiorly
- ) Inferiorly
- ) Thyroid cartilage
2. ) Cricoid cartilage
The thyroid cartilage and Cricooid cartilage are attached to the hyoid bone via the
Thyohyoid membrane and circohyoid membrane respectively
The superior border of the Thyroid cartilage corresponds to the
C4 vertebra
The cricoid cartilage is signet shaped with the band facing anteriorly. It is attached:
- ) Superiorly to the
- ) Inferiorly to the
- ) Thyroid cartilage
2. ) First tracheal ring
The cricoid cartilage corresponds with the
C6 vertebra
What are the two most significant joints in the neck?
Atlantooccipital and Atlantoaxial joints
The articulation between the occipital condyles and the superior articular facets of the atlas
Atlantooccipital joint
The atlantooccipital joint is supported anteriorly by the
-superior continuation of the posterior longitudinal ligament
Tectorial Membrane
The atlantooccipital joint is supported posteriorly by the
Atlantooccipital membrane
Nodding of the head occurs at the
Atlantooccipital joint
The articulation between C1 and C2
Atlantoaxial joint
The atlantoaxial joint includes two zygopophyseal joints and the articulation between the
Dens of C2 and the anterior arch of C1
The articulation involving the dense is a pivot typed synovial joint also called the “no joint” because it is used to
Turn the head from side to side
Important ligaments of the atlantoaxial joint (no joint) include the
-Help resist dislocation of the dens , which could injur the spinal cord
Transverse ligament of the atlas and alar ligaments
Muscles of the neck can be organized into which three groups?
- ) Superficial
- ) Deep
- ) Hyoid
What are the three superficial neck muscles?
Platysma, Trapezius, and Sternocleidomastoid
The DEEP neck muscles can be organized into which three groups?
- ) Anterior
- ) Posterior
- ) Lateral
What are the two ANTERIOR muscles of the DEEP group?
- ) Longus capitus
2. ) Longus Coli
What are the two POSTERIOR muscles of the DEEP group?
- ) Semiuspinalis
2. ) Splenius etc
What are the muscles of the LATERAL group of the DEEP neck muscles?
1.) Anterior, middle, and posterior scalenese, and Levator Scapulae (LS)
The hydoid muscles can be organized into which two groups?
- ) Suprahyoid
2. ) Infrahyoid
Used in swalloing and phonation and assist in tongue movements
Hyoid muscles
Elevate the hyoid bone and voice box, helping to shorten the pharynx and close off the larynx during early stages of swallowing
Suprahyoid muscles
During phonation, elevation of the hyoid and voice box by suprahyoid muscles assists in the production of
High notes
Depress the hyoid bone and voice box, assisting in the production of low notes during phonations
Infrahyoid muscles
Helps steady the hyoid bone and provides a stable platform for the tongue to move upon
Simultaneous contraction of the hyoid
What are the 5 suprahyoid muscles?
- ) Stylohyoid
- ) Anterior belly of digastric
- ) Posterior belly of digastric
- ) Mylohyoid
- ) Geniohyoid
What are the 4 infrahyoid muscles?
- ) Omohyoid
- ) Sternohyoid
- ) Sternothyroid
- ) Thyrohyoid
The cervical fascia consists of both superficial and deep layers. However, the more clinically relevant layer is the
Deep layer
Provides natural cleavage planes for surgery, facilitates movement of visceral structures, and can contain and facilitate the spread of infectious pus
Deep cervical Fascia
The deep Cervical Fascia is organized into which three layers?
Investing, prevertebral, and pretracheal
Surrounds the entire neck and encloses both the prevertebral and pretracheal layers
Investing layer
Surrounds the trachea and thyroid gland, and continues posteriorly as the buccupharyngeal fascia covering the pharynx and esophagus
Pretracheal layer
Extension of pretrachial layer of deep cervical fascia that covers the pharynx and esophagus
Buccopharyngeal fascia
Thus, the pretracheal fascia creates a
Visceral compartment
Surrounds the deep neck muscles and the vertebral column
Prevertebral fascia
The investing layer attaches
- ) Superiorly to the
- ) Inferiorly to the
- ) Posteriorly to the
- ) Skull
- ) Sternum, clavicle, and scapula
- ) Spinous processes
Splits to enclose the trapezius muscle
Investing layer
The investing layer forms the fascial roof of the
Posterior triangle
Splits to enclose the omohyoid, sternocleidomastoid, and infrahyoid muscles
Investing layer
Pierce the investing layer of the deep cervical fascia
External jugular vein and cervical nerve
Covers the trachea, thyroid gland, and thyroid and circoid cartilages
Prethracheal layer
The prevertebral layer attaches posteriorly to the spinous processes and lies superficial to the
Scalene muscles
Anteriorly, the prevertebral layer of the deep cervical fascia becomes continuous with the
Anterior longitudinal ligament
Forms the fascial floor of the posterior triangle
Prevertebral layer
The prevertebral layer is elongated laterally by the subclavian artery and parts of the brachial plexus, forming ultimately the
Axillary sheath
A neurovascular compartment formed in part by the prethracheal, preverteral, and investing layers of fascia
Carotid sheath
The carotid sheath contains the
Common carotid artery, internal jugular vein, vagus nerve, and lymph nodes
Lies BETWEEN the investing and prevertebral fascia in the posterior triangle
Accessory nerve
Lies within the retropharyngeal space
Sympathetic trunk
Lies between the prevertebral fascia and the buccopharyngeal fascia (posterior part of pretrachial)
Retropharyngeal space
Clinically important because it extends throughout the neck into the thorax and can facilitate the spread of infection pus
Retropharyngeal space
An esophageal abcess that begins in the neck could spread within the retropharyngeal space into the
Superior mediastinum
What are the two major cervical arteries?
Subclavian artery and External carotid artery
The subclavian arteries give rise to branches in the neck that supply the
Deep neck, shoulder, and brain
Branches of the right and left subclavian artery anastomose with eachother as well as branches of the
External carotid artery
The external carotid artery branches from the common carotid artery at the level of the
C4 vertebral body
What are the two important sensory structures located at the bifurcatiuon of the carotid artery?
Carotid body and carotid sinus
Lies within the crotch of the bifurcation of the common carotid artery
Carotid body
Contains chemoreceptors that monitor O2 and CO2 content of the blood
Carotid body
A dilation in the wall of the internal carotid artery at the bifurcation
Carotid sinus
Contains pressoreceptors that monitor blood pressure
Carotid Sinus
The carotid body and carotid sinus are innervated primarily by branches of the
Glossopharyngeal Nerve
-Some input from Vagus nerve
Branches of the right and left external carotids anastomose with eachother and with branches of the
Subclavian arteries
The two major veins in the head and neck
Internal and External jugular veins
Begins at the external opening of the jugular foramen where it drains venous blood
Internal jugular vein
The internal jugular vein courses through the neck within the carotid sheath where it receives tributaries from both
Superficial and deep veins
The internal jugular vein ends inferiorly by joining the subclavian vein to form the
Brachiocephalic vein
The external jugular vein begins at the union of the
Posterior auricular and retromandibular veins
The external jugular vein drains superficial structures of the
Face, neck, and scalp
The external jugular vein crosses the posterior cervical triangle within the superficial fascia and pierces the investing fascia to drain into the
Subclavian vein
The nerves found within the neck are of what three types?
- ) Rami of cervical spinal nerves
- ) Cranial nerves
- ) The sympathetic trunk
Innervate deep posterior neck muscles
Dorsal rami of cervical spinal nerves
The ventral rami of cervical spinal nerves form which two plexuses?
Cervical plexus and Brachial plexus
The cervical plexus consists of ventral rami from
C1-C4
The cervical plexus form sensory nerves of the neck as well as the
Ansa cervicalis
Supplies motor innervation to the infrahyoid muscles
Ansa cervicalis
Also formed in the neck by C3, C4, and C5 ventral rami `
Phrenic Nerve
The phrenic nerve can be located lying anterior to the
Anterior scalene muscle
Lie in part within the neck
Cranial nerves IX, X, XI, and XII
The cervical portion of the sympathetic trunk is located within the retropharyngeal space immediately posterior to the
Carotid sheath
The Sympathetic Trunk typically contains which three ganglia?
- ) Stellate Ganglia
- ) Middle CervicalGanglia
- ) Superior cervical ganglia
Formed by the fusion of the first thoracic ganglion and the inferior cervical ganglion
Stellate Ganglion
The stellate ganglion is connected to the
- ) T1 Ventral ramus (by grey and white ramus communicans)
2. ) C7 nd C8 ventral rami (via grey ramus communicans only)
Connected to the C5 and C6 ventral rami via gray rami communicans
Middle Cervical Ganglion
Connected to C1- C4 ventral rami via gray rami communicans
Superior Cervical Ganglion
Superiorly comes off the superior cervical ganglion and forms a plexuson the internal carotid artery
Internal carotid nerve
ALL of the cell bodies of post ganglionic sympathetic neurons that supply the head are located in the
Superior cervical Ganglion
The primary route of lymphatic drainage is via deep cervical nodes that are located along the
Internal jugular Vein
These nodes drain into the jugular lymph trunks which drain into the
Right lymphatic duct and Thoracic duct
These ducts typically drain into the venous system at the union of the
Internal jugular and subclavian vein
What are the two endocrine glands located in the neck?
Thyroid and parathyroid glands
The thyroid and parathyroid glands are both richly supplied with blood via
Inferior and superior thyroid arteries
Connects the two lobes of the thyroid gland
Isthmus
What are the 5 cervical branches of the external carotid artery?
- ) Superior thyroid artery
- ) Ascending Pharyngeal artery
- ) Occipital Artery
- ) Lingual Artery
- ) Facial Artery
The superior thyroid artery branches into the
Superior Laryngeal Artery
The superior thyroid artery/superior laryngeal artery supply the
Thyroid gland and larynx
The facial artery supplies the
Face
The occipital artery supplies the
Posterior deep neck and scalp
The lingual artery supplies the
Oral cavity
The ascending pharyngeal artery supplies the
Pharynx, deep neck, and face