Download Muscluar triangles of the neck

Muscluar triangles of
……………….the neck
BY: DR. AYAT
ELDOMOUKY
POSTERIOR TRIANGLE
BOUNDARIES
Trapezius muscle
Sternomastoid
muscle
clavicle
POSTERIOR TRIANGLE
Boundaries:
- In front → Posterior border of sternomastoid m.
- Behind → Anterior border of trapezius m.
- Apex → Middle ⅓ of superior nuchal line.
- Base → Middle ⅓ of the clavicle.
Roof
- Skin.
- Superficial fascia.
- Deep (investing) fascia of the neck.
The superficial fascia of the posterior triangle contains the following :
(1) Platysma m. : (a subcutaneous m.)
(2) External Jugular vein
(3)The cutaneous branches of the cervical plexus
Floor: From below upwards:
a) Scalenus medius. b) Levator scapulae. c) Splenius capitis.
Contents:
Arteries
1- Third part of subclavian a.
2- Suprascapular a.
3- Superficial (or transverse) cervical a.
4- Occipital a. (near the apex).
Veins
5- Subclavian v., receiving its only tributary, the external jugular v.
Nerves
6- Roots and trunks of brachial plexus.
7- Spinal accessory n. (runs on levator scapulae).
L.Ns.
8- Occipital L.N. (at the apex with the occipital a.).
9- Supraclavicular L.N. (at base with the subclavian a.).
Ms.
10- Inferior belly of omohyoid .
OMOHYOID MUSCLE
DIVISION OF POSTERIOR TRIANGLE
Occipital triangle
Supra
clavicular
ANTERIOR TRIANGLE
ANTERIOR TRIANGLE
□ Boundaries :
• Anteriorly → Middle line of the neck.
• Posteriorly → Ant. border of sternomastoid.
• Base (above) → Lower border of mandible.
• Apex (below) → Suprasternal notch.
□ Roof:
1- Skin.
2- Superficial fascia (+ its contents).
3- Investing ( deep ) fascia.
Contents of the Superficial Fascia of the Roof:
a- Platysma muscle.
b- Transverse cervical n.
c- Anterior jugular v. : It is formed by the union of the submental veins → descends
in the superficial fascia near the middle line → pierces the deep fascia above the
sternum → passes deep to the sternomastoid → ends in the external jugular v. The
deep parts of both anterior jugular veins are connected together by jugular arch.
□ Subdivisions : 3 ½ triangles . See the table .
DIGASTRIC MUSCLE
Suddivisions
of ANTERIOR
TRIANGLE
Suprahyoid muscles
1-MYLOHYOID
MUSCLE
Mylohyoid line
2- stylohyoid muscles
Inferior mental spine
3- geniohyoid
Recall of relevant structures
The suprahyoid muscles
the muscles of the floor of the mouth
Infrahyoid
muscles
Enumerate main contents of
submandibular triangule and give
short account on one of them
Muscles: suprahyoid muscles
(mylohyoid muscle), geniohyoid,
stylohyoid, digastric and hyoglossus muscles
2. Glands: submandibular salivary glands &
L.N.
3. Nerves: nerve to mylo-hyoid muscle,
hypoglossal nerves and Submandibular
ganglion
4. Vessels: facial artery& vein
1.
Enumerate main contents of
submandibular region and give short
account on one of them
Muscles: 1:suprahyoid muscles
(mylohyoid muscle), geniohyoid,
stylohyoid, digastric and hyoglossus muscles
2:genioglossus
1. Glands: submandibular salivary glands & L.N.
Sublingual salivary gland
1. Nerves: nerve to mylo-hyoid muscle,
hypoglossal nerves and Submandibular ganglion
Lingual nerve
1. Vessels: lingual & facial vessels
1.
Facial vessels
Submandibular ganglion
Lingual nerve
Sublingual salivary gland
Hypoglossal nerve
Lingual vessels
Nerve to mylohyoid muscle
Submandibular salivary gland
suprahyoid muscles
Muscle
Origine
Insertion
Nerve supply
action
Digastric muscle
post. belly: Mastoid
process of temporal
bone
ant. belly:
Body of mandible
Intermediate tendon is
held to hyoid by fascial
sling
post. belly: facial nerve
ant belly: nerve to
mylohyoid
Depresses mandible or
elevates hyoid bone
Mylohyoid muscle
Mylohyoid line of body
of mandible
Body of hyoid bone
and fibrous raphe
Inferior alveolar nerve
Elevates floor of mouth
and hyoid bone or
depresses mandible
Hyoglossus muscle
Hyoid bone
Post. ½ of the side of
the tongue
Hypoglossal nerve
Draw the tongue
downwards and help
suckling
Geniohyoid
Genial tubercle of the
mandible
Body of hyoid bone
Hypoglossal nerve
Depresses mandible or
elevates hyoid bone
Styloyoid
Styloid process
Hyoid bone
Facial nerve with post.
Belly of digastric
Elevate hyoid bone
Enumerate main contents of carotid
triangule and give short account on one
of them
1. Carotid sheath: CCA, ICA, IJV and
2.
3.
4.
5.
6.
vagus nerve
External carotid artery
Hypoglossal nerve
Ansa cervicalis
Accessory nerve
Sympathetic trunk
ANSA CERVICALIS
• It is a nervous loop situated in front of the carotid
sheath.
• It is formed by union of 2 limbs :
A) Superior limb : Descending from the hypoglossal
n. and containing fibers of C1 spinal nerve .
B) Inferior limb : From C2 and C3 spinal nerves .
• Branches : arise from the tip → supply all
infrahyoid muscles (near their lower ends) except
thyrohyoid.
Enumerate main contents of muscular
triangule and give short account on one
of them
Infra hyoid muscles
Enumerate main contents of submental
triangule and give short account on one
of them
1. Submental LN
2. Anterior jugular vein