Sternomastoid Sternomastoid muscle Sternocleidomastoid muscle Origin by 2

Sternomastoid

Sternomastoid muscle Sternocleidomastoid muscle * Origin: by 2 heads: Sternal head: from the front of manubrium sterni. - Clavicular head: from the upper surface of the medial 1/3 of the clavicle. * Insertion: (1) Lateral surface of mastoid process. (2) Lateral 1/3 of superior nuchal line. * Nerve supply: Spinal part of accessory nerve * Actions: 1 - When one muscle contracts: a- bends the head towards its same side. b- Rotates the face to the opposite side. 2 - Both muscles flex the neck.

Roof Apex Posteriorly Trapezius muscle Skin and fascia that contain platysma and external jugular vein Anteriorly Sternomastoid Base Middle 1/3 of clavicle Boundaries of posterior Triangle

Semispinalis capitis Splenius capitis Levator scapulae Scalenus medius muscle Floor of Post. triangle Inferior belly of omohyoid

** Contents of the posterior triangle: - Nerves: 1) Spinal part of the accessory nerve. 2) Roots and trunks of the brachial plexus. 3) Cervical plexus and its branches. - Arteries (OTTS): 1) Occipital artery. 2) Third part of Subclavian artery. 3) Transverse cervical artery. 4) Suprascapular artery. - Veins: 1) External jugular vein. 2) Subclavian vein.

Mastoid process Bas eo Boundaries of ant. triangle fm and ible Midline Anterior triangle Sternocleidomastoid Clavicle Sternum

* Origin; from the deep fascia covering the pectoralis major and deltoid muscles. * Insertion, into the lower border of the mandible and skin of the face. * Nerve supply, facial nerve. * Action, tenses the skin of the neck. Platysma muscle

Lower border of mandible Anterior belly of digastric Posterior belly of digastric Superior belly of omohyoid Anterior border of Sternomastoid Midline Subdivision of anterior Triangle in the neck

Floor of the anterior triangles Mylohyoid muscle

Digastric muscle * Origin: it has 2 bellies: (1) Anterior Belly: from the digastric fossa on the lower border of mandible close to symphysis menti. (2) Posterior belly: from the medial surface of the mastoid process. * Insertion: into intermediate tendon which is connected to the hyoid bone by a fibrous loop. * Nerve supply: (1) Anterior Belly: by nerve to mylohyoid (from 1 st pharyngeal arch). (2) Posterior belly: by facial nerve (from the 2 nd pharyngeal arch). * Action: (1) Depresses the mandible (opening the mouth). (2) Elevates the hyoid bone during swallowing.

* Contents of submandibular triangle : (1) Submandibular gland. (2) Submandibular ganglion. (3) Submandibular lymph nodes. (4) Facial artery. (5) Common facial vein. (6) Hypoglossal nerve. (7) Lingual nerve.

* Contents of submental triangle 1 - Submental artery. 2 - Submental vein. 3 - Submental lymph nodes.

* Contents of the carotid artery : (1) 3 carotid arteries Common, Internal and External carotid artery (2) Internal jugular vein (3) Last 3 cranial nerves, 10 th (Vagus) , 11 th (Spinal root of accessory nerve) and 12 th (Hpoglossal nerve). (4) Ansa cervicalis infront the carotid sheath. (5) Cervical sympathetic chain behind the carotid sheath.

SUBMANDIBULAR GLAND Type; It is a mixed Salivary gland (mucous and serous). Aspects and position (Parts): 1) a large superficial part. 2) A small deep part. - The two parts are continues with each other at the posterior border of the mylohyoid muscle.

Shape C-shaped 2 Parts Small deep part Mylohyoid muscle Large Superficial part Loop communication Submandibular gland

Submandibular (Wharton's) duct Length: 5 cm long. Origin; - It arises from the medial surface of the superficial part. End, It opens into the floor of mouth close to the frenulum of the tongue

Position Sublingual gland Mucous membrane of mouth Sublingual gland Sublingual fossa Mylohyoid line

SUBLINGUAL SALIVARY GLAND Site: It lies under the mucous membrane of the floor of the mouth forming sublingual fold in the sublingual fossa of mandible. Size: it is the smallest of the 3 salivary glands. Shape: almond shaped. Ducts: about 10 -20 ducts which open into floor of mouth along the sublingual fold.

GENERAL INVESTING DEEP FASCIA - It surrounds the neck like a collar. - It forms the roof of the anterior and posterior triangles. - It splits to enclose the sternomastoid and trapezius

• Pretracheal fascia * Site; It lies deep to the infra-hyoid muscles. It covers the front and side of trachea and encloses the thyroid gland. • CAROTID SHEATH * Definition: it is a tubular sheath Contenting : (1) Common carotid artery (below) and internal carotid artery (above). (2) Internal jugular vein. (3) Vagus nerve. • PREVERTEBRAL FASCIA - It is a firm sheet which lies in front of the prevertebral muscles. - It extends downward to surround the subclavian artery and trunk of the brachial plexus forming the axillary sheath to the apex of the axilla. • BUCCOPHARYNGEAL FASCIA - It covers the outer surface of the buccinator muscle.

Th ank Qu you est ion s I/Azzam - 2004