1. Posterior Triangle of the Neck
Dr. Lubna Nazli

2. Objectives Describe the anatomy of posterior triangles of neck
List the fascial layers of neck, and the major structures that they enclose
Identify major neurovascular structures in the neck, including external / internal jugular and subclavian veins, common / external / internal carotid and subclavian arteries, proximal brachial plexus, cervical plexus, and lymphatics

3. Cervical Fascia Consists of: 1- superficial fascia
2- deep cervical fascia
a. superficial (investing) layer
b. pretracheal layer
c. prevertebral layer

4. Superficial Cervical Fascia
- immediately deep to the skin of the neck
- encloses the platysma muscle
- is continuous with that of the head and thorax
- It contains
A. cutaneous nerves,
B. superficial Lymph nodes,
C. superficial vessels,
D. fat

5. 1- investing fascia Deep cervical fascia
-surrounds all structures in the neck
- between superficial fascia and the muscles
-splits to enclose the trapezius and Sternocleidomastoid muscles
-splits superiorly to enclose the parotid and submandibular glands

6. *Suprasternal Space
space between the 2 layers of deep fascia just above the manubrium which encloses
sternal head of Sternomastoid
Inf. end of the anterior jugular veins
jugular venous arch
fat
few lymph nodes

10. 2-pretracheal fascia - limited to the anterior part of the neck
- completely surrounds the thyroid gland
- forming a sheath for the thyroid gland
- binds the gland to the larynx

11. pretracheal fascia
encloses the parathyroid glands, trachea, pharynx, esophagus and Infrahyoid muscles
inferiorly blends with the fibrous pericardium
laterally with the carotid sheath
superiorly attaches to the thyroid cartilage and hyoid bone

13. 3-Prevertebral fascia
tubular sheath for the vertebral column and its related muscle
from base of the skull to T3, where it fuses with the anterior longitudinal ligament of the thoracic vertebrae
extends laterally as the axillary sheath

14. Retropharyngeal Space
-the largest and most important interfascial space in the neck
-It is a potential space consisting of loose connective tissue
-it is between
1-prevertebral fascia, and
2-Bucchopharyngeal fascia ( covers the pharynx
superficially and the buccinator muscle)
-Closed superiorly by the base of the skull
-Opens inferiorly into the superior mediastinum
-Permits the movements of the pharynx, larynx, esophagus,
and trachea during the swallowing
Infection in the retropharyngeal space may
extend inferiorly into the Superior mediastinum

15. Triangles of the neck

16. SCM
divides the neck Into
2 triangles
1-anterior
2-posterior

17. Posterior Triangle of the Neck
Boundaries:
Anterior border
posterior border of
the SCM
Posterior border
anterior border of the
trapezius muscle
Base
intermediate 1/3 of the clavicle
Apex
meeting of the anterior
and posterior border

18. Roof 1-skin 2-the superficial fascia which contains a) platysma
b) external jugular vein
c) cutaneous branches
of the cervical plexus
3-the deep fascia

19. Floor 2- levator scapula 3- scalenus posterior 4- scalenus medius
1- splenius capitis
2- levator scapula
3- scalenus posterior
4- scalenus medius
5- scalenus anterior
All covered by
the prevertebral fascia
Small part of the semispinalis muscle may appear at the apex of the triangle

20. 2- subclavian triangle (supraclavicular)
*subdivided by the inferior belly of the omohyoid muscle
Into : 1-occipital triangle
2- subclavian triangle (supraclavicular)

21. Occipital
triangle
Inferior belly of omohyoid
Supraclavicular
triangle

22. Occipital triangle Bounded by – Anterior border of trapezius muscle
– Posterior border of sternocleidomastoid muscle
– inferior belly of omohyoid

23. Supraclavicular triangle
Bounded by
– Omohyoid muscle
– The clavicle
– Sternocleidomastoid muscle

24. *Contents
A-Muscles the inferior belly of the omohyoid m

25. B-nerves *Accessory nerve
Descends on the surface of the levator scapulae
*Nerves to the levator scapulae
from the ventral rami of C3 and C4
*Cutaneous branches of the cervical plexus

26. B-nerves *Roots and trunks of the brachial plexus
Supraclavicular nerve
Suprascapular nerve
Dorsal scapular nerve
Long thoracic nerve
Nerve to subclavius

27. veins arteries -Transverse cervical vessels -Suprascapular vessels
-Subclavian artery
crossing the first rib
veins
External jugular vein

29. Platysma muscle Origin deep fascia that covers
the pec major and deltoid ms
Insertion
into the lower border of
the mandible
some fibers to the Face
which blend with the muscle
at the angle of the mouth
Nerve supply
cervical branch
of facial nerve
Action
-depresses the mandible
-draws down the lower lip

30. Omohyoid muscle: Origin Inferior belly
upper margin of the scapula medial
to suprascapular lig.
Superior belly
lower border of body of hyoid bone
Insertion
intermediate tendon ( clavicle and 1st rib by facial sling)
Nerve supply
Ansa Cervicalis (C1,2 and 3)
Action
depresses hyoid bone

31. Sternocliedomastoid(SCM)
Origin
manubrium and medial 1/3 of the clavicle
(sternal head and Clavicular head))
Insertion
mastoid processes of temporal bone
and occipital bone
Nerve supply
1-spinal part of the
accessory nerve (motor)
2-C2 and C3 (sensory)
Action
-two muscles acting together
extend the head and flex
the neck
-one muscle rotates
head to opposite side

32. What is torticollis?
Torticollis (wry neck) is a congenital or acquired condition of limited neck motion in which the child will hold the head to one side with the chin pointing to the opposite side.
It is the result of the shortening of the sternocleidomastoid (neck) muscle.
In early infancy, a firm, non-tender mass may be felt in the midportion of the muscle. The mass will go away and be replaced with fibrous tissue.
If untreated, there can be permanent limitation of neck movement. There may be flattening of the head and face on the affected side.

34. The veins: -External jugular vein:
begins just behind the angle of the mandible
-it is deep to the platysma muscle
-is formed by union of
1-Posterior Auricular vein
2-Post. Division of the Retromandibular v.
- drain into the subclavian vein.

35. Retromandibular vein
Is formed by the superficial temporal and maxillary veins
Divides into
an anterior branch, which joins the facial vein to form the common facial vein, and
a posterior branch, which joins the posterior auricular vein to form the external jugular vein

36. Tributaries of EJV . Posterior auricular vein
. Post.division of the Retromandibular vein
. transverse cervical vein,
. suprascapular vein
. anterior jug.vein

37. *Superficial cervical LN
-lie along the external jugular vein in the posterior triangle, and along the anterior jugular vein in the anterior triangle
-superficial to the SCM
-Drains into deep cervical LN
-Receives Lymph vessels from the
occipital and mastoid LNs

38. a rudimentary cervical rib a tight fibrous band first thoracic rib
The brachial plexus and subclavian artery may be compressed in the neck by
a rudimentary cervical rib
a tight fibrous band
first thoracic rib
a tight scalenus anterior muscle
giving rise to sensory,
motor
vascular symptoms
in one or both upper extremities.

39. cervical rib
Pressure in the region of a cervical rib will give rise to local pain as well as pain referred to the hand and arm particularly in the ulnar portion of the hand and forearm since it is the lower trunk of the brachial plexus which is involved (C8,T1). There is muscular weakness of the small hand muscles.

40. Nerves: B-The branches of the Cervical Plexus
A-The Accessory nerve
B-The branches of the Cervical Plexus
C-The Roots and the Trunks
of the Brachial Plexus

41. Nerves:

42. What structures are contained within the posterior triangle of the neck?
Posterior triangle of neck
Muscles ( SCM, Trapezius, Omohyoid & floor muscles)
Accessory nerve
3 trunks of brachial plexus
Cervical plexus
External jugular vein
Subclavian artery
Deep cervical lymph nodes (what is Virchow’s node? )