Download Deep Cervical Fascia

Surface anatomy
Plan fascia of the neck
Dr. H.A.Jaafar
Al-Nahrain Universitycollege of Medicine
Dept. Of Anatomy
Objectives:
we should be able to know :
1.The subcutaneous tissue nerves, veins of the neck,
2.The main anatomical potential space in the neck which lead to Spread
Infections to the mediastinum.
3.Three major fascial compartments of the neck
4.Where the viscera of the neck are located.
The Neck
•
•
lies between lower margin of mandible above &
suprasternal notch & upper border of clavicle below.
It is strengthened by cervical part of vertebral column,
•
•
is convex forward
supports skull.
Behind the vertebrae is ………………….a mass of extensor muscles
in front is …………………………………..a smaller group of flexor muscles .
In central region are :…………………parts of respiratory system,
larynx & trachea,
behind are parts of alimentary system, pharynx & esophagus.
At sides of these structures are vertically running :
1.
2.
3.
4.
carotid arteries,
internal jugular veins,
vagus nerve,
deep cervical lymph nodes
Landmarks of the neck
• Sternocleidomastoid
• Suprasternal fossa
• Greater supraclaviclar fossa
Landmarks of the neck
• Hyoid bone
• Thyroid cartilage
• Cricoid cartilage
Skin of Neck
lines of cleavage of skin are constant
 run …..horizontally …..around neck.
an incision :


along a cleavage line will heal as a narrow scar,
crosses lines will heal as a wide or heaped-up scar.
The natural line of cleavage of the skin are
constant and run almost horizontally
around the neck
Fascia of Neck
1-Superficial Fascia
2-deep Fascia
1-Superficial Fascia
Superficial Fascia
o forms a thin layer
o encloses platysma muscle.
embedded in it are :



cutaneous nerves,
superficial veins,
superficial lymph nodes.
Structures in neck:
 are surrounded by a layer of subcutaneous tissue (superficial fascia)
 are compartmentalized by layers of deep cervical fascia.

fascial planes determine direction in which an infection in neck may spread.
Cervical Subcutaneous Tissue &Platysma




superficial cervical fascia
is a layer of fatty connective tissue
lies between dermis of skin & investing layer of deep cervical fascia
It is usually thinner than in other regions, anteriorly.
It contains :
 cutaneous nerves,
 blood & lymphatic vessels,
 superficial lymph nodes
 variable amounts of fat.
 Platysma……..Anterolaterally
external jugular vein (EJV)
• descending from angle of mandible to middle of
clavicle
• are superficial to main cutaneous nerves of
neck.
• covers anterolateral aspect of neck.
Platysma
• flat plate is a broad, thin sheet of muscle in subcutaneous tissue of neck
• is supplied by cervical branch of CN VII.
• Its fibers arise in deep fascia covering superior parts of deltoid & pectoralis
major muscles
• sweep superomedially over clavicle to inferior border of mandible.
 anterior borders of the two muscles decussate over chin
blend with facial muscles.
Inferiorly, fibers diverge, leaving a gap anterior to larynx & trachea
• tenses skin,


•
producing vertical skin ridges
releasing pressure on superficial veins.
use in shaving
• in a grimace.
•
•
•
depress the mandible and draw corners of mouth inferiorly
Acting its inferior attachment
convey tension or stress.
Contents
• Platysma
• Superficial veins
– Anterior jugular v.
– External jugular v.
• Cutaneous nerves
–
–
–
–
Lesser occipital n.
Greator auricular n.
Transverse nerve of neck
Supraclavicular n.
• Cervical branch of facial n.
Regions of neck
• Neck
– Anterior region of neck
– Sternocleidomastoid region
– Lateral region of neck
Triangles of posterior (lateral)
region of neck
Occipital triangle
supraclavicular triangle
(greater supraclavicular fossa)
2-Deep Cervical
Fascia
Deep Cervical Fascia:
1.investing,
2.pretracheal, &
3.prevertebral.
support :
1.
2.
3.
4.
viscera (thyroid gland),
muscles,
vessels, &
deep lymph nodes.
condenses around : ………



to form
carotid sheath
common carotid arteries,
internal jugular veins (IJVs), &
vagus nerves
form natural cleavage planes

tissues may be separated during surgery,
•
limit the spread of abscesses (collections of pus)
afford slipperiness
allows structures in neck to move and pass over one another without difficulty,
swallowing and turning the head and neck.
Deep Cervical Fascia:
1.investing,
Investing Layer
most superficial deep fascial layer,
surrounds entire neck deep to skin and subcutaneous tissue.
splits into superficial and deep layers to enclose (invest) :
1.
2.
trapezius &
sternocleidomastoid (SCM) muscles.
Superiorly, attaches to :






Superior nuchal line of occipital bone.
Mastoid processes of temporal bones.
Zygomatic arches.
Inferior border of mandible.
Hyoid bone.
Spinous processes of cervical vertebrae.
also splits to enclose :
submandibular gland;
posterior to mandible, it splits to form fibrous capsule of parotid gland.
Investing Layer
stylomandibular ligament is a thickened modification
Inferiorly, attaches to :




manubrium,
clavicles, &
acromions
spines of scapulae.
continuous posteriorly
with :
 periosteum covering C7 spinous process,
 nuchal ligament
 a triangular membrane
 forms a median fibrous septum between muscles of two sides of neck
Deep Cervical Fascia:
pretracheal,
Pretracheal Layer of Deep Cervical Fascia
is limited to the anterior part of neck
It extends inferiorly from hyoid into thorax,
it blends with the fibrous pericardium covering heart.
includes a thin muscular part,
encloses :
 infrahyoid muscles, &
 a visceral part,
encloses




thyroid gland,
trachea, &
esophagus
pharynx
is continuous posteriorly & superiorly with buccopharyngeal fascia of pharynx.
blends laterally with carotid sheaths.
Pretracheal Layer of Deep Cervical Fascia
In hyoid,
a thickening of pretracheal fascia forms a pulley or trochlea through
intermediate tendon of digastric muscle passes,
 suspending hyoid.
tethers two-bellied omohyoid muscle,
redirecting course of muscle between bellies.
Prevertebral Layer
forms a tubular sheath for vertebral column & muscles associated
with it,
such as :
A.
B.
C.
longus colli &longus capitis anteriorly,
scalenes laterally,
deep cervical muscles posteriorly
is fixed to cranial base superiorly.
Inferiorly, it blends with endothoracic fascia peripherally
fuses with anterior longitudinal ligament centrally
at approximately T3 vertebra
extends laterally as axillary sheath
surrounds axillary vessels & brachial plexus.
sympathetic trunks cervical parts are embedded in it
Carotid Sheath
is a tubular fascial investment
extends from cranial base to root of neck.
blends :
 anteriorly with investing and pretracheal layers
 posteriorly with prevertebral layer
contains :
(1)
(2)
(3)
(4)
(5)
(6)
common and internal carotid arteries,
internal jugular vein,
vagus nerve (CN X),
deep cervical lymph nodes,
carotid sinus nerve,
sympathetic nerve fibers (carotid periarterial plexuses).
carotid sheath and pretracheal fascia communicate freely with:


mediastinum of thorax inferiorly &
cranial cavity superiorly.
represent potential pathways for spread of infection and extravasated blood.
Retropharyngeal
Space
is largest and most important interfascial space in neck
It is a potential space
consists of loose connective tissue between visceral part of prevertebral layer of deep
cervical fascia & buccopharyngeal fascia surrounding pharynx superficially.
Inferiorly, buccopharyngeal fascia is continuous with pretracheal layer
alar fascia :
•
•
•
forms a further subdivision of retropharyngeal space.
is attached along midline of buccopharyngeal fascia from cranium to level of the C7
vertebra.
it extends laterally and terminates in carotid sheath.
permits movement of pharynx, esophagus, larynx, and trachea Sternocleidomastoid
relative to vertebral
column during swallowing.
Investing layer of deep cervical fascia
Pretracheal fascia
(visceral part)
Caro
tid
sheat
h
is closed :
 superiorly by cranial base and
 on each side by carotid sheath.
T
E
Buccopharyngeal
fascia
Prevertebral fascia
Trapezius
Deep Cervical Fascia
Pretrach
eal
fascia
(muscula
rAlar
part)fascia
Posterior cervical triangle
Anterior triangles
Suprahyoi
dmuscles
Infrrahyoid
muscles
Trapezius
Sternocleidomastoid
Investing layer of deep cervical fascia
Pretracheal fascia
(visceral part)
Carotid
sheath
T
E
Sternocleidomastoid
Pretracheal
fascia
(muscular
part)
Prevertebral muscles
Alar fascia
Buccopharyngeal
fascia
Prevertebral fascia
Trapezius
Deep Cervical Fascia
Scalene muscles
Trace the pathways for venous drainage from the neck into the brachial
veins.
Sup. thyroid
Ext. jugular
Int. jugular
Middle
thyroid
Inf. thyroid
Ant. jugular
Platysma
Cutaneous nerves and superficial veins
Lesser occipital n.
External jugular vein
Greet auricular n.
Transverse nerve of neck
Anterior jugular vein
Supraclavicular n.
Submendibular gland
Digastric
Accessory n.
Hypoglossal n.
Superior thyroid a.
Ansa cervicalis
Sternothyroid
Sternohyoid
Vagus n.
Cervical plexus
Phrenic n.
Omohyoid