Neck Region
PA 481
Anterior Surface
Triangles at Surface
Hyoid
1. C3 level
2. Suprahyoid muscles
3. Infrahyoid muscles
Vertebral Column
Intervertebral disc
Vertebra
Parts
C1 & C2
Cervical Vertebra
Typical Cervical Vertebra
Spinal Cord
• Receives and
generates signals to
body through the
spinal nerves
Cord in Spinal Canal
Posterior Median
Sulcus
Posterior
Root
Denticulate
Ligament
Dorsal Root
Ganglion
Anterior
Root
Spinal Nerve
Spinal Cord (X.S.)
Spinal Cord (x.s.)
Spinal Nerve Anatomy
Functional Arrangement of SC
Ascending and descending pathways
Ascending Pathways
Descending Pathways
Cervical Plexus
Serves neck and
diaphragm
Brachial Plexus and pectoral nerves
Brachial Plexus
Innervates
most of the
arm and some
of the body
wall.
Spinal Cord Segments
• 4 segments: Cervical,
Thoracic, Lumbar, and
Sacral (only 1
coccygeal nerve)
• 31 pairs of spinal
nerves
Cervical Segment
Neck Fascia
Superficial fascia
Prevertebral fascia
Alar fascia
Pretracheal fascia
Investing fascia
Platysma
SCM and Trapezius
SCM
Trapezius
Cervical Triangles
Posterior Triangle
Anterior Triangle
Posterior Triangle
Occipital triangle
Supraclavicular triangle
Superficial and Deep Posterior Triangle
Ext. jugular v.
SCM
Splenius
Levator scapulae
Accessory n.
Nerve Point
of Neck
Phrenic n.
Prevertebral fascia
Platysma
Scalenes
Brachial
plexus
Supraclavicular Triangle
Brachial Plexus
SCM
Subclavian vessels
Anterior Triangles
Submandibular
Submental
Carotid
Muscular
Muscular Triangle
Muscles of Triangle
Thyrohyoid
Sternothyroid
Thyroid
Sternohyoid
Thyroid Location
Accessory
Thyroid gland
Accessory thyroid
along thyroglossal
duct
Pyramidal lobe
(50% of people have this lobe structure)
Thyroid Follicle
(follicular cells  thyroxine)
Parafollicular cells  calcitonin
T3 & T4 Formation and Secretion
T3 & T4
Control of Thyroxine Secretion
Short loop
Long loop
Thyroid Malfunction
• Hypothyroidism
• Endemic goiters –due to iodine
deffeicency
• Cretinism –i thyroxine in child
results in igrowth (dwarf) and
severe mental retardation
• Myxedema –i thyroxine in adult,
leads to swelling of tissues plus
other symptoms
Cretinism
Thyroid Malfunction
• Hyperthyroidism
• Toxic goiters (Graves disease) –Ab
may stimulate thyroid without
negative feedback control
• Exophthalmos –symptom present in
many hyperthyroid patients
Parathyroid Location
Parathyroid
PTH Actions
• Stimulates resorption of
bone  hCa+ and PO4- in
blood
• Stimulates Ca+ absorption in
intestine (active Vit. D3
necessary for Ca+
absorption)
• Stimulates Ca+ reabsorption
and PO4- excretion in kidney
• Stimulates Vit. D3 formation
(skin) and activation
(kidney)
• Vital for life
Laryngeal Cartilages
Hyoid
Epiglottis
(anterior)
Arytenoid
cartilage
Thyroid cartilage
Cricoid cartilage
(posterior)
Voice Box
Vestibular fold
Ventricle
Vocal fold
CN X: supply to laryngeal muscles
Inf. Vagal ganglion
Internal Laryngeal n.
(sensory & autonomic)
External Laryngeal n.
(motor to inf. Pharnygeal
constrictor and the cricohyoid)
Recurrent Laryngeal n.
(motor to all other
laryngeal muscles)
Digastric
Mylohyoid
Submental Triangle
-contains submental lymph nodes
Carotid Triangle
Digastric (posterior belly)
External carotid a.
Internal carotid a.
Common carotid a.
Ansa cervicalis
SCM
IJV
Omohyoid
Ext. Carotid Branches
Hypoglossal n.
Occipital
Post. Auricular
Int. carotid
Superficial Temporal
Maxillary
Ext. carotid
Facial
Lingual
Sup. Thyroid
IJV
Common Carotid
Ansa cervicalis
Asc. Pharyngeal (not show)
External carotid (isolated)
Superficial Temporal
Post. Auricular
Maxillary
Occipital
Facial
Lingual
Asc. Pharyngeal
Sup. Thyroid
Note: Internal carotid has NO neck branches.
Carotid bodies
IJV
Sup. Bulb of IJV
Facial
Sup. Thyroid
Inf. Bulb of IJV
IJV
Lymph nodes of neck
Deep Cervical Lymph nodes
(most located in carotid sheath)
Submandibular Triangle
Submandibular glands
Digastrics
Submandibular Lymph nodes
Pharynx
Function: deglutition
Mucosa: Str. Squamous
Muscularis: Skeletal
Oro- and nasopharynx
Pharyngeal tonsil
Pharyngotympanic
(Eustachian) tube
Tubal tonsils (small holes)
Pharyngeal recess
Palatine bone
Salpingopharyngeal fold
Soft palate
Uvula
Palatoglossal arch
Tonsillar cleft
Palatopharyngeal arch
Lingual Tonsil
Longitudinal pharyngeal muscles
Palatopharyngeus
Tonsils
Pharyngeal
Tonsil
Pharyngeal Constrictors
Superior
Middle
Inferior
Peristalsis
Deglutition (Swallowing)
Fluid Drinking
Deglutition (cont’d)
Deglutition (cont’d)
Laryngopharynx
Epiglottis
Piriform recess