Neck Anatomy Flashcards
Where is the anterior triangle located?
The front of the neck
What is the superior border of the anterior triangle?
Inferior border of the mandible
What is the lateral border of the anterior triangle?
Anterior border of sternocleidomastoid
What is the medial border of the anterior triangle?
Sagittal line down the midline of the neck
What covers the roof of the anterior triangle?
Investing fascia
What covers the floor of the anterior triangle?
Visceral fascia
What are the contents of the anterior triangle?
Muscles
Nerves
Arteries
Veins
Lymph nodes
What are the suprahyoid muscles?
Stylohyoid
Digastric
Mylohyoid
Geniohyoid
What are the infrahyoid muscles?
Omohyoid
Sternohyoid
Thyrohyoid
Sternothyroid
What vascular structures are in the anterior triangle?
Common carotid- bifurcates into external carotid and internal carotid
Internal jugular vein
What cranial nerves are in the anterior triangle?
Facial (VII)
Glossopharyngeal (IX)
Vagus (X)
Accessory (XI)
Hypoglossal (XII)
What are the subdividsons of the anterior triangle?
Carotid triangle
Submental triangle
Submandibular triangle
Muscular triangle
What are the boundaries of the carotid triangle?
Superior: posterior belly of digastric muscle
Lateral: medial border of sternocleidomastoid muscle
Inferior: superior belly of omohyoid muscle
What are the main contents of the carotid triangle?
Common carotid triangle (bifurcates)
Internal jugular vein
Hypoglossal nerve
Vagus nerve
What are the boundaries of the submental triangle?
Inferior: hyoid bone
Medial: midline of neck
Lateral: anterior belly of digastric
What are the main contents of the submental triangle?
Submental lymph nodes
What are the boundaries of the submandibular triangle?
Superior: body of mandible
Anterior: anterior belly of digastric muscle
Posterior: posterior belly id digastric muscle
What are the main contents of the submandibular triangle?
Submandibular gland
Submandibular lymph nodes
Facial artery
Facial vein
What are the boundaries of the muscular triangle?
Superior: hyoid bone
Medial: midline of neck
Superolateral: superior belly of omohyoid muscle
Inferolateral: inferior portion of sternocleidomastoid
Where is the posterior triangle located?
Lateral aspect of the neck
What is the anterior border of the posterior triangle?
Posterior border of sternocleidomastoid
What is the posterior border of the posterior triangle?
Anterior border of trapezius muscle
What is the inferior border of the posterior triangle?
Middle 1/3 of clavicle
What covers the posterior triangle?
Investing layer of fascia
What forms the floor of the posterior triangle?
Prevertebral fascia
What muscles are in the posterior triangle?
Omohyoid muscle
Splenius capitis
Levator scapulae
Anterior scalene
Middle scalene
Posterior scalene
What vascular structures are in the posterior triangle?
External jugular vein (crosses sternocleidomastoid)
Subclavian vein and artery
Transverse cervical vein and artery
Suprascapular vein and artery
What nerves are in the posterior triangle?
Accessory nerve (XI)
Cervical plexus -> phrenic nerve
Brachial plexus
What are the subdivisions of the posterior triangle?
Occipital triangle
Subclavian (Omo clavicular) triangle
Separated by omohyoid muscle
What are the characteristic features of cervical vertebrae?
Triangular vertebral foramen
Bifid spinous process
Transverse foramina
What are the features of the atlas?
No vertebral body
No spinous process
Lateral masses
- Superior articular facet
- Inferior articular facet
Anterior arch
Transverse ligament
What are the features of the axis?
Dens (odontoid process)
Superior articular facets
What is the joint between vertebral bodies?
IV disc
Fibrocartilagenous- symphysis
What is the joint between vertebral arches?
Synovial type joint
What type of joint is the atlanto-occipital?
Condyloid type synovial
What type of joint is the atlanto-axial?
Lateral (x2): synovial plane
Medial: synovial pivot
Where does the hyoid bone lie?
Base of the mandible (C3)
What are the components of the hyoid bone?
Body
Greater horn
Lesser horn
What are the muscular attachments to the hyoid bone?
Oral cavity and pharynx: Middle pharyngeal constrictor, Hypoglossus, Genioglossus
Suprahyoid: Digastric, Stylohyoid, Geniohyoid, Mylohyoid
Infrahyoid: Thyrohyoid, Omohyoid, Sternohyoid
What are the ligaments that attach to the hyoid bone?
Stylohyoid ligament
Thyrohyoid membrane
Hyoepiglottic ligament
What is the location of the thyroid gland?
Anterior neck
C5-T1
What is the structure of the thyroid gland?
Left and right lobe
Central isthmus
What are the anterior relations of the thyroid gland?
Infrahyoid muscles
What are the lateral relations of the thyroid gland?
Carotid sheath: common carotid artery, internal jugular vein, vagus nerve
What are the medial relations of the thyroid gland?
Larynx
Pharynx
Trachea
Oeosphagus
External laryngeal and recurrent laryngeal
What is the arterial supply of the thyroid gland?
Superior thyroid artery (first branch of external carotid artery)
Inferior thyroid artery (branch of thyrocervical trunk)
What does the superior thyroid artery lie in close proximity to?
External branch of superior laryngeal nerve
What does the inferior thyroid artery lie in close proximity to?
Recurrent laryngeal nerve
What do parathyroid glands produce?
Parathyroid hormone- increases level of serum calcium
Where is the parathyroid gland located?
Posterior aspect of thyroid gland
2 superior
2 inferior
What is the innervation of the parathyroid glands?
Thyroid branches of cervical ganglia
What is the action of the suprahyoid muscles?
Elevate the hyoid bone
What are the attachments of the Stylohyoid muscle?
Origin: Styloid process of temporal bone
Insertion: Lateral aspect of hyoid bone
What is the innervation of the Stylohyoid muscle?
Stylohyoid branch of facial nerve (VII)
What are the attachments of the Digastric muscle?
Anterior belly: Digastric fossa of mandible
Posterior belly: mastoid process of temporal bone
The 2 bellies are connected by an intermediate tendon which is attached to the hyoid bone via a fibrous sling
What is the innervation of the Digastric muscle?
Anterior belly: inferior alveolar nerve, a branch of mandibular nerve (CNV3)
Posterior belly: Digastric branch of facial nerve (VII)
What are the attachments of the Mylohyoid muscle?
Origin: Mylohyoid line of mandible
Insertion: hyoid bone
What is the innervation of the Mylohyoid muscle?
Inferior alveolar nerve, a branch of mandibular nerve (CNV3)
What are the attachments of the Geniohyoid muscle?
Origin: inferior mental spine of the mandible
Insertion: Hyoid bone
What is the innervation of the Geniohyoid muscle?
C1 nerve roots that run within the hypoglossal nerve (XII)
What are the 2 divisions of the infrahyoid muscles?
Superficial: omohyoid, sternohyoid
Deep: sternothyroid and thyrohyoid
What are the attachments of the Omohyoid muscle?
Inferior belly: scapula
Superior belly: hyoid bone
The 2 bellies are attached by an intermediate tendon which is anchored to the clavicle by the deep cervical fascia
What is the innervation of the Omohyoid muscle?
Anterior rami of C1-C3
What are the attachments of the Sternohyoid muscle?
Origin: sternum
Insertion: Hyoid bone
What is the innervation of the Sternohyoid muscle?
Anterior rami of C1-C3
What are the attachments of the Sternothyroid muscle?
Origin: manubrium of sternum
Insertion: Thyroid cartilage
What is the innervation of the Sternothyroid muscle?
Anterior rami of C1-C3
What are the attachments of the Thyrohyoid muscle?
Origin: thyroid cartilage of larynx
Insertion: hyoid bone
What is the innervation of the Thyrohyoid muscle?
Anterior ramus of C1, carried within hypoglossal nerve
Where is the cervical plexus located?
Posterior triangle of the neck
Within the prevertebral layer of cervical fascia
What forms the cervical plexus?
Anterior rami of C1-C4
What are the main muscular branches of the cervical plexus?
Phrenic nerve (C3-C5)
Nerves to geniohyoid and thyrohyoid (C1)
Ansa Cervicalis (C1-C3)
What are the sensory branches of the cervical plexus?
Greater auricular nerve (C2-C3)
Transverse cervical nerve (C2-C3)
Lesser occipital nerve (C2)
Supraclavicular nerve (C3-C4)
What arteries supply the head and neck?
Carotid arteries
Vertebral arteries
At what level does the carotid artery bifurcate?
C4
Carotid triangle
What are the end branches of the external carotid artery?
Superficial temporal
Maxillary
Where does the external carotid artery end?
Within the parotid gland
What are the 6 branches of the eternal carotid artery?
Superior thyroid
Linguinal
Facial
Ascending pharyngeal
Occipital
Posterior auricular
Where does the internal carotid artery enter the cranial cavity?
Via the carotid canal in the temporal bone
What are the 3 main jugular veins?
External
Internal
Anterior
What 2 veins form the external jugular?
Posterior auricular
Retromandibular
What muscle does the external jugular vein run anterior to?
Sternocleidomastoid
What vein does the external jugular drain into?
Subclavian vein
What are the anterior jugular veins?
Paired veins
Where is the internal jugular vein located in the neck?
Within the carotid sheath
What are the 2 fascias in the neck?
Superficial cervical fascia
Deep cervical fascia
What does the superficial cervical fascia contain?
Neurovascular supply to skin
Superficial veins
Superficial lymph nodes
Fat
Platysma muscle
What are the layers of the deep cervical fascia? (superficial to deep)
Investing layer: surrounds all structures in neck
Pretracheal layer: spans between hyoid bone and thorax
Prevertebral layer: surrounds vertebral column and its associated muscles
Carotid sheaths
What are the contents of the carotid sheaths?
Common carotid artery
Internal jugular vein
Vagus nerve
Accompanying cervical lymph nodes
Where does the pharynx begin and end?
Begins at base of the skull
Ends at inferior border of cricoid cartilage (C6)
What are the parts of the pharynx?
Nasopharynx
Oropharynx
Laryngopharynx
What lines the nasopharynx?
Respiratory epithelium: ciliated pseudostratified columnar
What does the oropharynx contain?
Posterior 1/3 of tongue
Lingual tonsils
Palatine tonsils
Superior pharyngeal constrictor muscle
What is Waldeyer’s ring?
Ring of lymphoid tissue formed by:
- Palatine tonsils
- Adenoid tonsils
- Lingual tonsils
What does the laryngopharynx contain?
Middle and inferior pharyngeal constrictor muscles
What are the 2 main groups of pharyngeal muscles?
Longitudinal
Circular
What is the innervation of the muscles of the pharynx?
Vagus nerve
Except stylopharyngeus- glossopharyngeal nerve
What are the circular pharyngeal muscles?
Superior constrictor- oropharynx
Middle constrictor- laryngopharynx
Inferior constrictor- laryngopharynx
What are the longitudinal muscles of the pharynx?
Stylopharyngeus
Palatopharyngeus
Salpingopharynegus
Where does the stylopharyngeus arise from?
Styloid process
Where does the palatopharyngeus arise from?
Hard palate
Where does the salpingopharyngeus arise from?
Eustachian tube
What is the innervation of the pharynx?
Pharyngeal plexus:
- Pharyngeal branches of IX
- Pharyngeal branches of X
- Branches from external laryngela nerve
- Sympathetic fibres from superior cervical ganglion
What is the arterial supply of the pharynx?
Ascending pharyngeal a.
Branches of facial a.
Branches of lingual and maxillary a.
What is the venous drainage of the pharynx?
Pharyngeal venous plexus -> IJV
What vertebrae does the larynx span?
C3 to C6
What are the 3 sections of the larynx?
Supraglottis
Glottis
Subglottis
Where is the supraglottis?
From inferior surface of epiglottis to vestibular folds
What are vestibular folds?
False vocal cords
What does the glottis contain?
Vocal cords
Where is the subglottis?
From inferior border of glottis to inferior border of cricoid cartilage
What lines the interior of the larynx?
Pseudostratified ciliated columnar epithelium
What lines the true vocal cords?
Stratified squamous epithelium
What is the vasculature of the larynx?
Super and inferior laryngeal arteries
Superior and inferior laryngeal veins
What is the innervation of the larynx?
Branches of vagus nerve:
- Recurrent laryngeal nerve
- Superior laryngeal
What are the unpaired laryngeal cartilages?
Thyroid
Cricoid
Epiglottis (elastic)
What are the paired laryngeal cartilages?
Arytenoid
Corniculate
Cuneiform
Where are the cuneiform cartilages located?
Within the aryepiglottic folds
What are types of soft tissue laryngeal folds?
Vocal folds
Vestibular folds
What ringed arrangement do the tonsils form?
Waldeyer’s ring
How are the tonsils classified?
Mucosa-associated lymphoid tissue (MALT)
- Contain T cells, B cells and macrophages
What tonsils form the Waldeyer’s ring?
Pharyngeal tonsil
2 tubual tonsils
2 palatine tonsils
Lingual tonsil
What is the epithelial covering of the lingual tonsil?
Stratified non keratinised squamous epithelium
What is the epithelial covering of the pharyngeal tonsil?
Ciliated pseudostratified epithelium
What is the epithelial covering of the tubal tonsils?
Ciliated pseudostratified epithelium
What is the epithelial covering of the palatine tonsils?
Stratified non keratinised squamous epithelium