Download Posterior triangle of the neck

Posterior triangle of the neck
 Deep fascia of the neck
 Boundary of posterior triangle
 Contents of posterior triangle: muscles, vessels, nerves
Dept. of Anatomy Zhou Hong Ying
Skeleton of neck & Important landmarks
 Cervical part of spinal
column
 Hyoid bone
 Cartilage of the
respiratory tracts larynx
and trachea
 lower border of
mandible & mandibular
angle
 Mastoid process
Bones and cartilages of neck
Landmarks
Palpate following structures
on your own neck:
Hyoid bone
Thyroid cartilage: laryngeal
prominence
Cricoid cartilage
Trachea
SCM
Superficial structure----platysma
Deep Fascia of the Neck
▪ investing layer ▪ pretracheal layer
▪ prevertebral layer ▪ alar fascia & carotid sheath
Deep fascia
Fascial Spaces of the Neck
▪ pretracheal space
▪ retropharyngeal space
▪ fascial space within prevertebral layer
▪ alar fascia connects the carotid sheathes
▪ buccopharyngeal fascia is the posterior portion of the
pretracheal layer
Superficial Muscles of the Neck
The Posterior Cervical Triangle
▪ occipital triangle
▪ supraclavicular triangle
Omohyoid Muscle & SCM
Boundaries of Posterior Cervical Triangle
• bounded by the SCM,
trapezius and middle third
of the clavicle
• Apex: SCM and trapezius meet on the superior nuchal line of the occipital
bone.
• A roof : investing layer of the cervical fascia.
• A floor: muscles covered by the prevertebral layer of the cervical fascia.
Boundaries of Posterior Cervical Triangle
Main contents in posterior △
• Muscles scalenus anterior, medius, posterior; levator scapulae,
splenius
•
Nerves : cervical plexus, brachial plexus (root of neck), and
accessory N.
• Vessels external jugular vein, subclavian a and its branches &
v (root of neck) and thyrocervical trunk
• Cervical lymph nodes .
Muscles in the Posterior Cervical Triangle
▪ omohyoid muscle
▪ muscles form the floor
- anterior scalene muscle
- middle scalene muscle
- posterior scalene muscle
- levator scapulae muscle
- splenius capitis muscle
The Scalene Muscles
The Structures of
Posterior Cervical Triangle
▪ nerves
- accessory nerve
- cervical plexus
- brachial plexus
▪ arteries
- subclavian artery
▪ veins
- subclavian vein
the external jugular vein
the junction of the posterior
auricular vein and the posterior
division of the retromandibular vein.
 crosses the SCM in the superficial
fascia, at a point about 3~5cm above the
clavicle, usually end by emptying into the
subclavian vein.
External Jugular Vein
▪ retromandibular vein
▪ posterior auricular vein
▪ transverse cervical vein
▪ suprascapular vein
▪ anterior jugular vein
Subclavian v.:
being continuous with axillary v.,
Ant. to the scalenus Ant.,
uniting with internal jugular v.
to form brachiocephalic v.
posterior to the sternoclavicular
joint
Arteries of posterior triangle
 Subclavian a.
Post. to the subclavian v.
Anteroinferior to the brachial
plexus in scalenus space
 Transverse cervical a.
from thyocervical trunk
superior to the clavicle
deep to the omohyoid
 Suprascapular a.
from thyrocervical trunk
Posterior to clavicle
Arteries of posterior triangle
The accessory nerve

CNⅪ
a motor nerve
supplies the sternocleidomastoid
muscle & the trapezius muscle

The accessory nerve
 crosses the posterior △ ,
superficial to the deep
fascia covering the floor
CNⅪ
Cervical nerve plexus
This plexus is formed by 1st to 4th cervical nerves.
The Cervical Plexus
Cutaneous Branches of the Cervical Plexus
▪ lesser occipital nerve
- the scalp posterior to auricle
▪ great auricular nerve
- the skin covering the parotid
gland & mandibular angle
▪ transverse cervical nerve
- the skin of anterior portion
of the neck
▪ superaclavicular nerves
- the skin of anterior thoracic
wall above the 2nd costal
space & of the shoulder
The phrenic N
 motor nerve supply the diaphragm
arises from the ventral primary rami
3rd 4th and 5th cervical N.
 sensory branches: the central part of
the pleural and peritoneum of the
diaphragm.
 Descends obliquely across anterior
scalenus.
Outline
Chief Contents of the Posterior Cervical Triangle
▪ nerves
- accessory nerve
- cervical plexus:
lesser occipital nerve
great auricular nerve
transverse cervical nerve
superaclavicular nerves
* phrenic nerve
- brachial plexus
▪ arteries
- transverse cervical artery
- superascapular artery
▪ veins
- external jugular vein
Dissection
Layers of Posterior
Cervical Triangle
Deep dissection
• The investing layer of the deep
cervical fascia has been
removed. Although the spinal
accessory nerve (CN XI) is
superficial to it, the brachial
plexus and motor nerves of the
cervical plexus run deep to the
prevertebral layer of deep
cervical fascia that covers the
floor of the triangle.