1. MBJ 1: cranium development, triangles of the neck

contents of subclavian triangle

-Three trunks of the brachial plexus -Nerve to serratus serratus anterior (C 5,6,7) -Nerve to subclavius (C 5,6) -Suprascapular Suprascapular nerve (C 5,6) -Third part of subclavian artery artery -Subclavian vein -Suprascapular artery -Lower part of external jugular vein -Supracalvicular lymph nodes

Arteries of Carotid Triangle

-common carotid artery: right side branch of brachiocephalic a. & left side branch of arch of aorta. -carotid sinus -carotid body -internal carotid artery -external carotid artery with its 5 branches; superior thyroid a., lingual a, facial a, ascending pharyngeal a, occipital a.

ansa cervicalis

-content of caroitid triangle -a loop of nerves formed by C1, C2, C3 -supplies infrahyoid muscles

Floor of carotid triangle

-hyoglossus m. -thyrohyoid m. -inferior & middle constrictor of pharynx

contents of the posterior part of digastric triangle

-lower part of parotid gland -external carotid a. -deep structures passing bet. ECA & ICA; styloglossus & stylopharyngeus m., glossopharyngeal nerve & pharyngeal branch of vagus, syloid process, part of parotid gland -deep structures; ICA, IJV, and vagus nerve

floor of digastric triangle of the neck

-mylohyoid m. -hyoglossus m. -middle constrictor m.

cranium bones of membrano-cartilaginous development

-occipital bone (above the superior nuchal line is membranous and the rest is cartlaginous) -sphenoid bone (lateral parts of greater wings and pterygoid processes are membranous and the rest is cartilagginous) -temporal bone (squamous and tympanic parts are membranous and petromastoid part and styloid process are cartilaginous) -mandible (condylar and corinoid process are cartilaginous and the rest are membranous)

roof of carotid triangle

-skin -superficial fascia containing; platysma, cervical branch of facial nerve, transverse, cutaneous nerve ofteh neck. -investing layer of deep cervical fascia

contents of occipital triangle

-spinal part of the accessory nerve -lesser occipital nerve (C2) -lesser auricular nerve (C2,C3) -transverse cervical nerve (C2,C3) -supraclavicular nerve (C3,C4) - nerve to levator scapulae (C3,C4) - C3,C4 proproceptive fibers to trapezius -dorsal scapular nerve (C5) -transverse cervical vessels -inconstant occipital aftery -external jugular vein -supraclavicular & occipital nodes along posterior border of sternocleidomastoid

contents of the anterior part of digastric triangle

-submandibular lymph nodes -submandible lymph nodes - sublingual nerve & submandibular ganglion -facial vein -submental artery -mylohyoid nerve & vessels -hypoglossal nerve intermediate tendon of digastric with stylohyoid.

nerves of carotid triangle

-vagus: superior laryngeal with its external & internal laryngeal branches -spinal part of accessory nerve -hypoglossal nerve -sympathetic chain

boundaries of occipital triangle

Ant- posterior border of sternocleidomastoid post- anterior border of trapizius apex- meeting point of strenocleidomastoid & traoezius at teh superior nuchal line base- inferior belly of omohyoid

anterior triangle of the neck boundaries

ant- anterior median line of the neck post- anterior border of the sternocleidomastoid superiorly- inferior border of mandible and a line dawn from angle of mandible to mastoid process inferiorly- manubrium sterni

boundaries of posterior triangle of neck

ant- posterior border of sternocleidomastoid muscle post- anterior border of trapezius base- middle 1/3 of the clavicle apex- meeting point of the sternocleidomastoid & trapezius muscle at the superior nuchal line

boundaries of subclavian triangle

ant- stenocleidomastoid post- inferior belly of omohyoid apex- overlapping of sternoceidomastoid & inferior belly of omohyoid base- middle 1/3 of the clavicle

boundaries of carotid triangle of the neck

ant- superior belly of omohyoid m. post- anterior border of sternoceidomastoid m. superiorly- posterior belly of digastric m.

muscular triangle of neck boundaries

ant-anterior median line of neck from hyoid bone to the strenum posterosuperiorly-superior belly of omohyoid postero-inferiorly- anterior border of sternocleidomastoid m.

digastric triangle of the neck boundaries

anteriorinferiorly- anterior belly of digastric m. posteroinferiorly- postreior velly of diagastric and stylohyoid m. superiorly- inferior border of mandible & an imaginary line joining the angle of the mandible to the mastoid process

carotid triangle contains carotid sheath with its contents & which are

common carotid a internal carotid a internal jugular vein vagus nerve

lymph nodes of the carotid triangle

deep cervical lymph nodes - jugulo-diagastric & jugulo-omohyoid

cranium bones of cartilaginous development

ethmoid bone inferior nasal concha

floor of muscular triangle of neck is formed by

formed by sternohyoid & sternocleidomastoid

posterior triangle development

formed by the splitting of the posterior 6th brachial arch which forms the trapezius & sternocleidomastoid muscle

cranium bones of membranous development

frontal bone parietal bone maxilla (excluding promaxilla) zygomatic bone nasal bone lacrimal bone vomer

bones derived from the mesenchyme of neural crest:

frontal bone sphenoid bone lacrimal bone nasal bone zygomatic bone maxilla mandible hyoid

contents of muscular triangle of neck

infrahyoid muscles; stenohyoid, sternothyroid, thyrohyoid & omohyoid

Veins in carotid triangle

internal jugular vein with it tributaries; -common facial vein -pharyngeal vein -lingula vein -superior thyroid vein

the cranium (skull) develops from?

mesenchyme around the developing brain

nerve supply of sternocleidomastoid muscle

motor- spinal part of accessory nerve proprioceptive in function- ventral rami of C2 and C3

cranium consists of?

neurocranium viscerocranium

submental triangle boundaries

on each side- anterior belly of diagastric m. base- body of hyoid bone apex- lies at teh chin or symphysis menti floor- 2 mylohyoid m. & their median raphe roof- skin, superficial fascia, investing layer of deep cervical fascia

omohyoid muscle origin, insertion & nerve supply

origin- inferior belly arises from upper border of scapula near suprascapular notch & adjoing part of suprascapular ligament insertion- superior belly is inserted to lower border of body of hyoid bone lateral to sternihyoid NS: -superior belly of omohyoid: descendens hypoglossi -inferior belly of omohyoid: ansa cervicalis

thyrohyoid muscle origin, insertion & nerve supply

origin- oblique line of thyroid cartilage insertion-lower border of body & greater cornu of hyoid bone NS- C1 fibers

sternothyroid muscle origin, insertion & nerve supply

origin- posterior surface of manubrium sterni & adjoining part of 1st costal cartilage insertion- oblique line on the lamina of thyroid cartilage NS-ansa cervicalis

Sternohyoid muscle origin, insertion & nerve supply

origin-posterior surface of maubrium sterni insertion- medial part of lower border of hyoid bone NS- ansa cervicalis

sternocleidomastoid muscle origin and insertion

origin: - sternal head - tendinous and arises from the supero-lateral part of the front of fthe manubrium sterni - clavicular head - arises from medial 1/3 of the superior surface of the clavical. insertion: - lateral surface of the mastoid process

bones derived from paraxial mesoderm:

parietal bone occipital bone petrous part of temporal bone

superficial fascia of the roof of the posterior triangle contains

platysma external jugular vein posterior external jugular vein transverse cervical vessels suprascpular vessels cutaneous nerves; -lesser occipitak nerve (C2)-greater auricular nerve (C2,C3) -transverse cervical nerve (C2,C3) -supraclavicualr nerve (C3,C4)

posterior triangle of neck roof and floor

roof- skin, superficial fascia with its contents and investing layer of deep cervical fascia stretching between sternocleidomastoid and trapezius floor- formed by prevertebral layer of deep cervical fascia covering the following muscles; above downwards; -semispinalis capitis, -splenius capitis, -levator scapulae, -scalenus posterior, -scalenus medius, -scalenus anterior, -first rib & -first digitation of serratus anterior.

roof of digastric triangle of the neck

skin superficial fascia investing layer of deep crevical fascia.

roof of muscular triangle of neck is formed by

skin, superficial fascia with its contents investing layer of deep cervical fascia

posterior triangle of neck subdivisions

subdivided by the inferior belly of omohyoid into: -smaller lower subclavian or supraclavicular triangle -larger upper occipital triangle

submental triangle contents

submental lymph nodes anterior jugular veins

the anterior triangle of the neck is subdivided by the digastric and superior belly of the omohyoid into:

submental triangle digastric triangle carotid triangle muscular triangle

function of infrahyoid muscles

they function to bring about depressionof hyoid bone following its elevation during swallowing and vocal movements

Sternocleidomastoid actions

turns face to opposite side draws the head forward