anterior triangle of the neck Flashcards
what vessels sit in the superficial fascia
the superior veins
= anterior jugular veins
infrahyoid muscle
sternohyoid = C2, C3
omohyoid = C2, C3
thyrohyoid = C1
sternothyroid = C2, C3
what nerves innervate the muscles of the infrahyoid
C1
C2
C3
ansa cervicalis loop
- only motor
Ansa Cervicalis
superior root formed by C1 and inferior root formed by both C2 and C3
provides innervation to the infra hyoid muscles
thyrohyoid = only innervated by C1 (superior root)
what structure sits just behind the infrahyoid muscles
thyroid gland
where does the thyroid isthmus sit
in front of the 2nd and 3rd tracheal cartilage
arterial supply to the thyroid and their origin
- superior thyroid artery (from external carotid)
- inferior thyroid arteries (from subclavian)
venous drainage of the thyroid gland
- superior (drains to internal jugular vein)
- middle (drains to left brachiocephalic vein)
- inferior (drains to left brachiocephalic vein)
ima artery
present in some patients and comes from the isthmus of the thyroid
lymphatic drainage of the thyroid
paratracheal and deep cervical lymph nodes
sympathetic innervation of the thyroid
middle cervical ganglion
parasympathetic innervation of the thyroid
vagus (recurrent laryngeal nerve)
what sits lateral to the thyroid lobes
carotid sheath, containing the common carotid, vagus and internal jugular vein
- common carotid sits closest to the thyroid lobe
what nerve sits between the trachea and oesophagus
recurrent laryngeal nerve
embryology of the thyroid
thyroid grows down from the foramen caecum at the base of the tongue as the thyroglossal.
thyroid outgrowths from embryology and their locations
lingual thyroid = tongue
accessory thyroid tissue = between tongue and hyoid bone
cervical thyroid = just below thyroid bone
pyramidal thyroid = outgrowth from thyroid
supra hyoid muscles
- stylohyoid
- digastric (most anterior)
- mylohyoid
- geniohyoid (deepest)
what muscles does V3 innervate
- anterior belly of digastric and mylohyoid muscles
what innervates the geniohyoid
C1 (used to be one muscle with thyrohyoid)
internal carotid
has no branches within the neck!
what forms the external jugular veins
- posterior auricular vein
- retromandibular vein
course of the vagus nerve
exits the skull via foramen jugular (with CN 9,10,11)
travels through the carotid sheath beneath the IJV and internal carotid artery
at the root of the neck it stays close to the midline
