1. Muscluar triangles of ……………….the neck
By: DR. AYAT ELDOMOUKY

2. POSTERIOR TRIANGLE BOUNDARIES Trapezius muscle Sternomastoid muscle
clavicle

3. 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.

4. 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 .

5. OMOHYOID MUSCLE

6. DIVISION OF POSTERIOR TRIANGLE
Occipital triangle
Supra clavicular

7. ANTERIOR TRIANGLE

8. 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 .

9. DIGASTRIC MUSCLE

10. Suddivisions of ANTERIOR TRIANGLE

11. Suprahyoid muscles
1-MYLOHYOID MUSCLE
Mylohyoid line

12. 2- stylohyoid muscles 3- geniohyoid
Inferior mental spine

14. Recall of relevant structures
The suprahyoid muscles
the muscles of the floor of the mouth

15. Infrahyoid muscles

17. Important topics

18. 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
Glands: submandibular salivary glands & L.N.
Nerves: nerve to mylo-hyoid muscle, hypoglossal nerves and Submandibular ganglion
Vessels: facial artery& vein

19. 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
Glands: submandibular salivary glands & L.N.
Sublingual salivary gland
Nerves: nerve to mylo-hyoid muscle, hypoglossal nerves and Submandibular ganglion
Lingual nerve
Vessels: lingual & facial vessels

20. Facial vessels
Submandibular ganglion
Lingual nerve
Sublingual salivary gland
Hypoglossal nerve
Lingual vessels
Nerve to mylohyoid muscle
Submandibular salivary gland

21. 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
Styloyoid
Styloid process
Facial nerve with post. Belly of digastric
Elevate hyoid bone

22. Enumerate main contents of carotid triangule and give short account on one of them
Carotid sheath: CCA, ICA, IJV and vagus nerve
External carotid artery
Hypoglossal nerve
Ansa cervicalis
Accessory nerve
Sympathetic trunk

24. 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.

26. Enumerate main contents of muscular triangule and give short account on one of them
Infra hyoid muscles

28. Enumerate main contents of submental triangule and give short account on one of them
Submental LN
Anterior jugular vein