Download Posterior triangle of the neck

Posterior triangle of the neck
OUTLINE
•
Deep fascia of the neck
•
Boundary of posterior triangle
•
Structures of posterior triangle:
muscles, vessels, nerves
Dept. of Human Anatomy, Si Chuan University
Zhou hongying [email protected]
Bones
andofcartilages
of neck landmarks
Skeleton
neck & Important
 cervical vertebrae
 hyoid bone
 cartilage of larynx and trachea
 lower border of mandible &
mandibular angle
 mastoid process
Landmarks
Palpate following structures on your own
neck:
Hyoid bone
Thyroid cartilage: laryngeal
prominence
Cricoid cartilage
Trachea
SCM
Arrangements
Superficial structure----platysma
• in the subcutaneous
tissue
• supplied by the facial n.
Cervical Deep Fascia
▪ investing layer
▪ pretracheal layer
▪ prevertebral layer
▪ alar fascia & carotid
sheath
Cervical Deep Fascia
▪ investing layer
▪ pretracheal layer
▪ prevertebral layer
▪ alar fascia & carotid
sheath
Cervical Deep Fascial Spaces
Fascial Spaces of the Neck
▪ pretracheal space
▪ retropharyngeal space
▪ fascial space within prevertebral layer
Cervical Deep Fascia
▪ alar fascia connects the carotid sheathes
▪ buccopharyngeal fascia is the post-superior
portion of the pretracheal layer
Superficial Muscles of the Neck
▪ sternocleidomastoid m. /SCM
▪ trapezius
▪ (platysma)
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 & trapezius meet on the superior nuchal line of the occipital bone.
• Roof : investing layer of the cervical fascia.
• Floor: muscles covered by the prevertebral layer of the cervical fascia.
Boundaries of Posterior Cervical Triangle
Main structures of posterior △
• Muscles: scalenus anterior, medius,
posterior; levator scapulae, splenius
•
Nerves : cervical plexus, brachial
plexus (root of neck), 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 external jugular vein
the posterior auricular v. and the posterior
division of the retromandibular v.
crosses the SCM in the superficial fascia, at a point
about 3~5cm above the clavicle, usually end by
emptying into the subclavian v.
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
•
Transverse cervical a.
from thyocervical trunk
superior to the clavicle
deep to the omohyoid
•
Suprascapular a.
from thyrocervical trunk
Arteries of posterior triangle
Transverse cervical a.
Suprascapular a.
The accessory nerve CNⅪ
•
motor nerve
•
supplies the sternocleidomastoid
muscle & the trapezius muscle
The accessory nerve CNⅪ
•
crosses the posterior △,
superficial to the deep fascia
covering the floor
Cervical plexus
•
This plexus is formed by 1st to 4th cervical nerves.
Cutaneous Branches of the Cervical Plexus
▪ lesser occipital n.: - the scalp posterior to auricle
▪ great auricular n.: - the skin covering the parotid gland & mandibular angle
▪ transverse cervical n.: - the skin of anterior portion of the neck
▪ superaclavicular nerves: - the skin of anterior thoracic wall above the 2nd
costal space & of the shoulder
Cervical plexus
▪ consists of anterior rami of
the first 4 cervical nerves
▪ Sensory branches: lesser
occipital n., great auricular
n., transverse cervical n.,
superaclavicular nerves
 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.
The phrenic nerve
Outline
Chief Structures 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
• investing layer of the deep
cervical fascia has been
removed.
• prevertebral layer: accessory
nerve is superficial to it