Posterior Triangle Of Neck Flashcards
Skin on back of scalp and back of neck is supplied by
Dorsal rami of spinal nerves C2-C5
Dorsal rami of C1 and C6-C8 have no cutaneous distribution
Skin of anterior and lateral aspects of neck is supplied by
Ventral rami of C2-C4 spinal nerves via cutaneous branches of cervical plexus
They emerge from underneath the posterior border of sternocleidomastoid muscle
Cutaneous branches of cervical plexus
Lesser occipital nerve
Great auricular nerve
Transverse cervical nerve
Supraclavicular nerve
Lesser occipital nerve
Where is and what does it supply?
Follows the posterior border of sternocleidomastoid
Supplies skin over lateral part of occipital region and upper part of medial surface of muscle
C2, or C2,C3
Great Auricular Nerve
Ascends superficial to sternocleidomastoid, parallel to external jugular vein
Supplies skin over angle of mandible and parotid gland, and both surfaces of lower part of auricle
C2,C3
Transverse cervical nerve
Run Anteriorly, superficial to sternocleidomastoid
Supplies skin of anterior and lateral aspects of neck
C2, C3
Supraclavicular nerves
Arise from a common trunk, which divides into:
- medial supraclavicular nerve
- intermediate supraclavicular nerve
- lateral supraclavicular nerve
Descend into side of lower neck
Supply skin at base of neck and skin that covers upper part of pec. Major and deltoid muscles
Platysma
LOINA
L- muscle embedded in superficial fascia of neck
O- deep fascia that covers upper parts of pectoralis major and deltoid muscles
I- over side of neck into muscles of lower lip and angle of mouth
N- cervical branch of facial nerve
A- tenses skin of neck, helps depress mandible, draws down lower lip and angle of mouth
What does the external jugular vein divide into?
Posterior auricular vein and retromandibular vein
function of Posterior Auricular vein
Drains scalp posterior and superior to auricle
Dumps into EJV
Function of retromandibular vein
Formed within parotid gland by union of superficial temporal and maxillary veins
At lower end of gland it divides into anterior (joins facial) and posterior branches (joins posterior auricular vein)
Tributaries to EJV
Transverce cervical vein
Suprascapular vein
Anterior jugular veins
Anterior jugular vein
Begins in submental region by union of several small veins
Descends close to anterior midline, just superior to jugular (Supra stern also) notch of sternum, turn laterally and passes posterior (deep) to sternocleidomastoid, then drains into EJV
Right and left jugular veins are usually join midline by jugular venous arch
Sternocleidomastoid
LOIN
L: from sternum/clavicle into anterior and posterior triangles
O: anterior surface of manubrium of sternum AND superior surface of medial third of clavicle
-sternal head and clavicular head
I: two heads join and insert into mastoid process and lateral part of superior nuchal line
N: accessory nerve (motor) and branches from ventral rami of C2 and C3 spinal nerves
Actions of Sternocleidomastoid
Unilateral vs bilateral
Unilateral:
Lateral flexion of head and neck to same side of contracting muscle
Rotation of head and neck to opposite side of contracting muscle
Bilateral:
Draws head forward
Flexion of head and neck against resistance
If head is fixed, accessory muscle of inspiration