The document summarizes the anatomy of the neck, including its boundaries and contents. It describes the skin, fascia, muscles like the sternocleidomastoid, triangles including the anterior (submental, submandibular, carotid) and posterior (supraclavicular, occipital) triangles. It also discusses the carotid sheath containing major blood vessels and nerves, and salivary glands such as the submandibular and sublingual glands.

1. Neck & Its Triangles
Dr. Haydar Muneer salih

2. • Neck is that part of the body which
connects the head to the upper part
of trunk.
• Boundaries
Superior: Lower border of body of
mandible
Inferior: Suprasternal notch & Upper
surface of clavicle

4. Skin & Cutaneous Nerves
• The natural lines of cleavage of the
skin run almost horizontally around
the neck.
• The skin overlying the back of the
neck and on the back of the scalp as
high as the vertex is supplied
segmentally by posterior rami of
cervical nerves 2 to 5.

5. 1. The greater occipital nerve (C2)
2. Cervical plexus branches (C2-C4)
A. The lesser occipital nerve (C2)
B. great auricular nerve (C2 and C3)
C.Transverse cutaneous nerve (C2 and
C3)
D.Supraclavicular nerves (C3 and C4)

8. Superficial Fascia
• The superficial fascia of the neck forms a
thin layer that encloses the platysma
muscle. Also embedded in it are the
cutaneous nerves, the superficial veins,
and the superficial lymph nodes.
• The platysma muscle is a thin but clinically
important muscular sheet embedded in the
superficial fascia.

10. DEEP FASCIA OF NECK (DEEP
CERVICAL FASCIA)
It is well developed in the neck and consists
of three layers. These are, from exterior to
interior:
1. Investing layer: deep to the subcutaneous
tissue and platysma and surrounds the neck
completely like a collar
2. Pre-tracheal layer: lies over the trachea
3. Prevertebral layer: anterior to the
prevertebral muscles

13. Carotid Sheath
• The deep cervical fascia forms a tubular
sheath around the major vessels of the
neck, named the carotid sheath on each
side. It extends from the base of skull
above to the arch of aorta below, on each
side.
• Contents of Carotid Sheath
1. Common carotid artery in lower part and
internal carotid artery in upper part.
2. Internal jugular vein.
3. Vagus nerve.

16. Neck Triangles

17. STERNOCLEIDOMASTOID MUSCLE
It is an important, superficially placed
muscle on each side of neck and is seen as
a prominent band passing from above
downwards in the neck, when the neck is
turned to one side.
It divides The side of neck into anterior and
posterior triangles

19. Origin: It arises from two heads:
1.Sternal head
2.Clavicular head
Insertion: The fibers run upwards and
backwards and insert in two parts:
1. Lateral surface of mastoid, as a thick
tendon.
2. Lateral half of occipital bone, as a
thin aponeurosis

21. Neck Triangles
1. Anterior triangles
A. Submental triangle
B. Submandibular triangle
C. Carotid triangle
D. muscular triangle
2. Posterior triangles
A.Supraclavicular triangle
B.Occipital triangle

24. Submental triangle
On each side: Anterior belly of
digastric
Base: Body of hyoid bone
Apex: Chin or symphysis menti
Floor: It is formed by the mylohyoid

26. Submandibular Triangles
Antero-inferior : Anterior belly of digastric
muscle.
Postero-inferior : Posterior belly of
digastric muscle.
Base : Base of the mandible
Apex : Intermediate tendon of digastric m.
Floor: mylohyoid m., hyoglossus m. and
middle constrictor m.
Roof: It is formed by the investing layer of
deep cervical

28. Carotid Triangle
Superior : Posterior belly of digastric
Anterio-inferior : Superior belly of omohyoid
Posterior : Anterior border of
sternocleidomastoid m.
Roof : It is formed by investing layer of deep
cervical fascia.
Floor: It is formed by four muscles:
Thyrohyoid m., Hyoglossus m., Middle
constrictor of pharynx m., Inferior constrictor
of pharynx m.

30. Muscular Triangle
Anterior : Anterior midline of the neck
Antero-superior : Superior belly of the
omohyoid.
Posterio-inferior : Anterior border of
sternocleidomastoid.

32. Posterior Triangle
Anteriorly: Posterior border of the
sternocleidomastoid
Inferiorly: Middle third of the clavicle
Posteriorly: Anterior border of the
trapezius
•Is subdivided into 2 triangles by the
omohyoid:
•Supraclavicular triangle
•Occipital triangle

33. Salivary Gland

34. Submandibular Salivary Gland
It is about half the size of the parotid gland
and lies below the mandible in the anterior
part of the digastric triangle.
• It consists of two parts, a large superficial
part and a smaller deep part, which lie
superficial and deep to the mylohyoid
muscle respectively.
• The two parts are continuous with each
other at the posterior border of mylohyoid
muscle.

37. SUBLINGUAL SALIVARY GLAND
• This is the smallest of the 3 pairs of
salivary glands.
• It lies immediately below the mucosa of the
floor of the mouth.
• it is rests in the sublingual fossa on the
inner aspect of the body of mandible.
• The gland pours its secretion by a series of
ducts, about 10 to 15 in number into the oral
cavity on the sublingual fold. Few ducts may
also open into the submandibular duct.