Anterior and posterior triangles of the neck Flashcards
what structures are found in the posterior compartment of the neck
spinal cord
vertebral column
muscles
cervical nerve
lateral compartments contents
carotid sheath
IVJ
vagus
common carotid
contents of the anterior compartment
thyoid, parathyroid, oesophagus, trachea
what is the motor innervation of trapezius and SCM
spinal accessory
what muscles form the boundaries of the lateral and anterior cervical regions/ posterior and anterior triangles
trapezius and sternocleidomastoid
what nerves supply pain and proprioception to trapezius and sternocleidomastoid
C2 and 3
what are the attachments of trapezius
lateral third of clavicle acromion spine of scapula occipital bone- superior nuchal line and external occipital protuberance nuchal ligament spinous processes (C7-T12)
what are the functions of trapezius
rotate the scapula during abduction of the humerus
elevate, adduct and depress the scapula
what are the functions of sternocleidomastoid
draws the head forwards, tilts and rotates the head
what are the attachments of sternocleidomastoid
mastoid process and superior nuchal line
sternum (manubrium)
medial third of clavicle
what are the boundaries of the posterior triangle of the neck
posterior border SCM
Ant border of trapezius
inf clavicle
apex where SCM and trapezius meet on the superior nuchal line
roof:investing layer
floor:muscles enclosed by prevertebral layer
where do trapezius and SCM meet superiorly
superior nuchal line
what covers the posterior triangle
skin and platysma
what forms the floor of the posterior triangle
muscles in the prevertebral column: splenius capitis levator scapulae posterior and middle scalene ant scalene is usually deep to SCM
where is middle scalene muscle
posterior tubercle of TP C5-7
1st rib, groove for subclavian
where is anterior scalene
transverse processes C3-C6
1st rib
what is the function of anterior scalene
nodding and side to side movements
what is the function of middle scalene
lateral flexion of the neck
what is the function of levator scapulae
fixes scapula, elevates and extends neck, lateral flexion of neck
what is the nerve supply to anterior scalene
C4-6
what are the three parts of subclavian artery in relation to anterior scalene muscle
medial
posterior
lateral
what is axillary fascia a continuation of
prevertebral layer of deep cervical fascia
what is the root value of the phrenic nerve (muscle supply)
c3, 4, 5
what is the root number of ansa cervicalis (muscle supply)
c1,2,3
what is the cervical plexus made of
anterior rami of c1-4
what is the lesser occipital nerve (cutaneous)
c2
greater auricular and transverse cervical nerves (cutaneous)
c2,3
supraclavicular nerves (cutaneous)
c3-4
what does ansa cervicalis innervate (c1-3)
infrahyoid muscles
what are the boundaries of the anterior triangle of the neck
median line of neck
anterior border SCM
inferior border of mandible
jugular notch of manubrium
what is the roof of the anterior triangle
subcutaneous tissue containing platysma
what is the floor of the anterior triangle
pharynx, larynx and thyroid gland
what is the innervation of platysma
cervical branch of facial nerve
where does the anterior belly of the digastric muscle attach to the hyoid
digastric fossa of mandible (V3)
what is the attachment of the posterior belly of the digastric muscle
mastoid notch of temporal bone (cn 7)
what are the attachments of stylohyoid
styloid process
greater wing of hyoid bone
cn 7
what are the attachments of geniohyoid
inferior mental spine of mandible
body of hyoid
what are the attachments of mylohyoid
mylohyoid line of mandible
body of hyoid
via V3
what does the submental triangle contain
submental lymph nodes and tributaries of ant juglular vein
what is the function of digastric
ant- elevates and steadies the hyoid bone when swallowing or speaking
what is the function of mylohyoid
elevates the hyoid and tongue when swallowing and speaking
what are the boundaries of the submental triangle
mandibular symphysis
anterior belly of digastric muscle
hyoid bone
mylohyoid muscle
what is the contents of the submandibular triangle
submandibular gland and submandibular lymph nodes
cn 12 and V3 branches
facial artery and vein
what are the borders of the submandibular triangle
inferior surface is the body of the mandible
posterior and anterior bellies of digastric muscle
what is the digastric sling
derived from pretracheal layers and allows digastric muscle to pass from ant to posterior
what are the borders of the carotid triangle
post belly of digastric muscle
sup belly omohyoid
ant border of SCM
At what level does the common carotid bifurcate
sup thyroid cartilage
what is the nerve supply to the carotid body
cn 11 and 10
what is the function of stylohyoid
elevates and retracts hyoid to elongate the floor of the mouth
what is the function of geniohyoid
shortens the floor of the mouth
what is the carotid sinus
baroreceptor
what is the carotid body
chemoreceptor
what are the attachments of thyrohyoid
oblique line of thyroid cartilage
inferior border of body and greater horn
C1 via hypoglossal n.
(CN XII)
what are the attachments of omohyoid
scapula
inferior border of hyoid
C1-C3 by branch of
ansa cervicalis
what are the attachments of sternohyoid
manubrium and medial clavicle
body of hyoid
C1-C3 by branch of ansa cervicalis
what is the effect of sternohyoid on the hyoid bone
depresses hyoid during swallowing
what is the effect of omohyoid
depresses retracts and steadies the hyoid
what is the function of thyrohyoid
depresses hyoid and elevates the larynx
what is the attachment of sternothyroid
posterior surface of manubrium
inserts on oblique line of thyroid cartilage
what is the function of sternothyroid
depresses hyoid and larynx
what is the innervation of sternothyroid
c2 and c3 by a branch of ansa cervicalis
what are the parts of the thyroid gland
pyramidal lobe
right and left lobes
isthmus
where is the thyroid gland
thyroid cartilage to 5th tracheal ring
visceral compartment of neck
what is the arterial supply to the thyroid gland
superior thyroid artery (1st branch of ext carotid)
inferior thyroid artery (branch of thyrocervical trunk from subclavian
what is the venous drainage of the thyroid
superior thyroid vein (IVJ)
middle thyroid vein (IJV)
inferior thyroid vein (brachiocephalic)
where are the parathyroid glands
posterior surface of thyroid gland
what is the blood supply of the parathyroid glands
inferior thyroid arteries
same venous drainage as thyroid
what does the external jugular vein drain into
subclavian
