Anatomy of the neckAnterior triangle - part 1

Dr. Mohamed El fiky

Professor of anatomy and Embryology

The Anterior Triangle,Infrahyoid Muscles,

Structures in the Midline of the Neck

Midline of the N

eck

The Anterior Triangle

Divisions of The Anterior Triangle

1- submental 2- digastric 3- carotid 4- Muscular

SkinSuperficial

FasciaAnterior

Jugular vein

PlatysmaInvesting ofDeep fascia

Roof of The Anterior Triangle

The Submental Triangle

Submentalartery

SubmentalLymph nodes

Submentalveins

Submental TriangleBoundaries :

Apex : symphysis menti.

Base : body of the hyoid bone

On each side : the anterior belly of the digastric muscle.

Floor: the two mylohyoid muscles with their median raphe.

Contents: 1.Submental lymph nodes 2. Submental vessels .

Digastric TriangleBoundaries:

Above : lower border of the mandible.Blow and in front : anterior belly of digastric.

Below and behind : posterior belly of digastric.

Floor : 1.Mylohyoid muscle : anteriorly.2.Hyoglossus muscle : posteriorly.

Contents : (A) Glands: 1. Submandibular gland.2. Part of the parotid gland.3. Submandibular lymph nodes.

(B)Vessels : 1. Facial artery : deep to the

submandibulr gland.2. Facial vein : superficial to the

submandibular gland.3. Submental artery :

superficial to the mylohyoid muscle.

4. Mylohyoid vessels : superficial to the mylohyoid muscle

(C) Nerve 1. Hypoglossal nerve : lies on

the hyoglossus and then disappears under the mylohyoid muscle.

2. Nerve to mylohyoid : superficial to the mylohyoid muscle.

CarotidTriangle

Hyoglossus

ThyrohyoidMiddle

andInferior

constrictor of

pharynxLongus Capitis

Carotid Triangle

4- Hypoglossal n.

3- Spinal accessory n.

1- Glossopharyngeal n.

2- Vagus n.

5- Ansa cervicalis

A- Arteries

1- Common carotid

2- External carotid

3- Internal carotid

4- Sup. Thyroid

6- Facial

5- Lingual

8- Ascendingpharyngeal

7- Occipital

B- Nerves

C-Veins

1- Internal jugular

2- Common facial

D- Lymph nodes

Upper and Lowerdeep cervical lymph nodes

Contents of Carotid Triangle

Boundaries : Behind : sternomastoid musclein front and above : posterior belly of digastric and stylohyoid muscles in frontand below : superior belly of omohyoidmuscle Floor : ØAnterior part : hyoglossus and thyrohyoid musclesØ Posterior part : middle and inferior constrictor muscles of the pharynx.

Contents : A) Vessels : 1- Common carotid artery. 2- Internal carotid artery. 3- External carotid artery and all its branches except the posterior auricular and the two terminal branches 3- Internal jugular vein and 3 of its tributaries (common facial , lingual and superior thyroid). B) Nerves: 1. Last 3 cranial nerves (vagus, spinal accessory and hypoglossal). 2. Cervical sympathetic chain .3. Ansa cervicalisC) Lymph nodes : deep cervical lymph nodes along the internal jugular vein.

Anteriorly: midline of the neck (from hyoid

bone to sternum).

Postero-superiorly:superior belly of omohyoid.

Postero-inferiorly: lower part of anterior border

of the sternomastoid.

Muscular or Thyroid Triangle

Boundaries : In front : median line of the neckbehind and above : superior belly of omohyoid. Behind and below : sternomastoid: Contents : infrahyoidmuscles which include:• Sternohyoid. • Omohyoid.• Sternothyroid.• Thyrohyoid.

Omohyoid m.Sternohyoid m.

Sternothyroid m.

Thyrohyoid m.

Infrahyoid Muscles

The infrahyoid muscles are ribbon-

like and arranged in two layers:

a. Superficial layer:

u Sternohyoid (medially)

v Superior belly of omohyoid

(laterally)

b. Deep layer :

uSternothyroid (below)

uThyrohyoid (above)

The Ansa Cervicalis

Mylohyoid Raphe

Body of Hyoid Bone

Hyoid Bursa

Thyrohyoid Membrane

Thyroid Cartilage

Cricothyroid Ligament

Cricoid Cartilage

Cricothyroid Muscle

First Ring of TracheaIsthmus

of Thyroid Gland

Trachea

Levator Glandulae Thyroidae

Suprasternal Notch or Space

Median Structures of the Neck

Anterior Jugular Veins

Jugular Arch

Inferior Thyroid Veins

Thyroidae Ima Artery

Left Brachiocephalic Vein

BrachiocephalicArtery