The neck region Flashcards
Superior thoracic aperture
Opens directly into the base of the neck
Axillary inlets
openings on each side to the upper limb
Anterior and posterior bones and cartilage
Posterior: cervical vertebrae
Anterior bone: Hyoid, manubrium, clavicles
Anterior cartilage: thyroid cartilage and trachea
How many cervical vertebrae are there ?
7 cervical vertebrae
How many cervical spinal nerves are there ?
8 cervical spinal nerves
Which cervical vertebrae are typical?
C3-C6
Which cervical vertebrae are atypical?
C1,C2,C7
General characteristics of a typical cervical vertebrae.
- small body
- large vertebral foramen(often triangle shaped)
- transverse foramen
- bifid(split or 2 parts) spinous process
C7 vertebra description
Called vertebra prominens
- long spinous process
- not bifid AKA normal/single process
- smallest transverse process
C1 vertebra structure
C1 is the ATLAS
- Lacks body
- lacks spinous process
- forms atlanto-occipital joint
C1 vertebra function
- Allows for flexion and extension(some lateral flexion
- Anterior and posterior atlanto-occiptial membranes provide broad support and prevent excessive movement
C2 vertebra structure
- Has a body
- bifid spinous process
- the dens(odontoid process)
C2 vertebra description and function
C2 is the AXIS
- Forms the atlantoaxial join with C1
- three articulations with the atlas(right and left lateral atlanto-axial, median atlanto-axial joint)
- Rotation between C1-C2
- Strong ligaments hold the dens in place
Alar ligament
Side of dens to foramen magnum
Transverse ligament
extends between tubercles in the medial aspect of C1 vertebra
Cruciate ligament
formed by transverse ligament and its superior/inferior extensions
Hyoid bone
C3 vertebral level
no bony articulation
suspended by muscles and ligaments (Stylohyoid) and bound to the thyroid cartilage by the thyrohyoid membrane.
Function: serves as a strong attachment site for anterior neck muscles.
Laryngeal cartilages
levels C3-C6
Protects air passages and involved in voice production
-nine cartilages(3 single cartilages and 3 pairs)
Thyroid gland
Produces calcitonin and thyroid hormone
deep to infrahyoid muscles
large unpaired gland with two lobes and a connecting isthmus.
thyroid gland blood supply
Superior thyroid artery: off of the external carotid artery
inferior thyroid artery: largest branch of the thyrocervical trunk
Sternocleidomastoid(attachments)
Lateral superior nuchal line and mastoid process to:
- Medial third of clavicle
- anterior surface of manubrium
Sternocleidomastoid(innervation)
Motor: Accessory nerve(CNXI)
Sensory: C2 and C3
Sternocleidomastoid (action)
Unilateral action: Lateral flexion to the same side and rotation to the opposite side
Bilateral action: cervical flexion
Trapezius(attachment)
Skull, scapula and clavicle
Trapezius(Innervation)
Motor: CN XI
Sensory: C2 and C3
Anterior scalene(attachment and action)
attachment: Transverse process of C4-C6 to 1st rib
action: flex the neck and elevate first rib
Anterior scalene(innervation)
Cervical spinal nerves C4-C6
Middle scalene(attachment and action)
attachment: Transverse process of C4-C6 to 1st rib
action: flex the neck LATERALLY and elevate first rib
Middle scalene(innervation)
Ventral rami cervical nerves
Posterior scalene(attachment and action)
Transverse process of C4-C6 to 2nd rib
Lateral flexion and elevate 2nd rib
Posterior scalene(innervation)
Ventral rami of C6 and C7 cervical nerves
Omohyoid(attachments and innervation)
Superior scapula(omo) to hyoid bone Innervation: C1-C3(ansa cervicalis
Sternohyoid (attachments and innervation)
Manubrium and medial clavicle to hyoid
innervation: C1-C3 (ansa cervicalis)
Sternothyroid (attachments and innervation)
Manubrium to thyroid cartilage
innervation: C2-C3 by a branch of the ansa cervicalis
Thyrohyoid(attachments and innervation)
Thyroid cartilage to hyoid bone
C1 via hypoglossal nerve
what are the strap muscles’ collection action
depress the hyoid during swallowing and speaking
Thyrohyoid also elevates the larynx
Mylohyoid (attachments and innervation)
Mylohyoid line of the mandible to the hyoid bone
innervation: nerve to the mylohyoid (CNV3)
Geniohyoid (attachments and innervation)
Deep to mylohyoid
mental spine of the mandible to the hyoid
Innervation: C1 via hypoglossal nerve
Anterior belly of the digastric (attachments and innervation)
Digastric fossa of the mandible to the intermediate tendon
innervation: nerve to mylohyoid (V3)
Posterior belly of the digastric (attachments and innervation)
Mastoid notch to the intermediate tendon
innervation: Facial nerve (CN VII)
Stylohyoid (attachments and innervation)
Styloid process of the temporal to hyoid
innervation: facial nerve CNVII
Suprahyoid muscle action
The suprahyoid make a portion of the floor of the mouth(support)
Elevate the hyoid and larynx
Cervical plexus(location and origin)
Formed by anterior rami of C1-C4
Lies deep to SCM
what are the main subdivision of the cervical plexus and their general function
Superficial branches
-Cutaneous innervation
Deep branches
-motor innervation(ansa cervicalis)
What are the cutaneous branches of the cervical plexus?
- lesser occipital nerve
- great auricular nerve
- transverse cervical
- supraclavicular
Lesser occipital nerve(origin and innervation)
Contribution from C2
innervates skin of neck and scalp behind the ear
Great auricular nerve(origin and innervation)
Branches from C2-C3
innervates skin over parotid gland, sheath of parotid gland and skin of auricle
Transverse cervical (origin and innervation)
Branches from C2-C3
skin of the anterior neck region
Supraclavicular (origin and innervation)
Branches from C3-C4
Skin across clavicles and shoulder to the second rib
What does the ansa cervicalis supply?
Motor to infrahyoid muscles
Hypoglossal nerve
CNXII
Motor innervation to the tongue muscles except palatoglossus
Cell body in the medulla, exits skull via hypoglossal canal
passes external carotid artery and jugular vessels
Motor fibers from C1(come C2) to the hyoid muscles( geniohyoid and thyrohyoid)
Spinal accessory nerve
CNXI
Spinal root-cell bodies in the anterior horn of the upper cervical segments of the spinal cord
Rootlets ascend into the cranial cavity via foramen magnum.
Cranial root- part of cranial nerve X
The two roots unite at the jugular foramen the separate.
CNXI descends along the ICA picks up sensory from C2 & C3
Provides motor and sensory(C2-C3)innervation to the SCM and trapezius.
What part of the body does the thoracic trunk drain?
Everything but the upper right quadrant
What part of the body does the Right lymphatic trunk drain?
The upper right quadrant
Where do the thoracic duct and right lymphatic trunk drain?
Into the subclavian at the junction of the IJV
what do the jugular trunks drain?
The neck and head
what do the subclavian trunks drain?
The upper extremities
What are the component of lymphatic drainage of the neck and head?
Superficial nodes around the head superficial nodes along the external jugular vein paratracheal nodes retropharyngeal nodes infrahyoid nodes
what do the occipital nodes drain?
Posterior scalp and neck
what do the mastoid nodes drain?
the posterolateral half of scalp
what do the Preauricular and parotid nodes drain?
anterolateral scalp and upper half of face
what do the submandibular nodes drain?
follows facial vein drainage- anterior face, gingiva teeth tongue
what do the submental nodes drain?
lower lip, chin floor of mouth, tip of tongue and lower incisor teeth
Superficial cervical lymph nodes (location and function)
Along the external jugular vein
Send lymphatic vessels toward the deep cervical nodes
Depp cervical nodes(divisions and location)
Jugulodigastric node
Jugulo-omohyoid node
Forms a chain at IJV
Describe the lymphatic drainage of the tongue
Root of the tongue==>superior deep cervical nodes(jugulodigastric)
medial body==>inferior deep cervical nodes(juguloomohyoid)
right and left lateral==> submandibular nodes
tip of tongue and frenulum ==> submental
Submental and submandibular drain into the inferior deep cervical nodes
Where do the teeth and gingivae lymphatic drain into?
submandibular, submental, and deep cervical nodes
what divides the anterior and posterior triangle?
The SCM
Boundaries of the posterior triangle
Posterior border of SCM
Anterior border of the trapezius
Clavicle
contents of the posterior triangle
Accessory nerve cervical plexus brachial plexus(trunks) EJV Subclavian artery/vein suprascapular artery cervical lymph nodes
Boundaries of the anterior triangle
Anterior border of the SCM
Inferior border of the mandible
midline of the neck
Subdivisions of the anterior triangle
muscular triangle
carotid triangle
submandibular triangle
submental triangle
Boundaries of the muscular triangle
SCM
Superior belly of the digastric
midline of the neck to the hyoid bone
contents of the muscular triangle
infrahyoid muscles thyroid gland
parathyroid gland
Boundaries of the Carotid triangle
SCM
Superior belly of the omohyoid
posterior digastric
contents of the carotid triangle
Carotid sheath hypoglossal nerve accessory nerve ansa cervicalis deep cervical lymph nodes
Boundaries of the submandibular triangle
anterior and posterior bellies of the digastric
inferior border of the mandible
contents of the submandibular triangle
submandibular gland hypoglossal nerve submandibular lymph nodes nerve to the mylohyoid facial artery and vein
Boundaries of the submental triangle
Right and left anterior belly of the digastric
hyoid bone
contents of the submental triangle
submental lymph nodes and veins
