Anterior triangle of the Neck Flashcards
External jugular is formed by?
Retromandibular vein and posterior auricular vein.
Where does the anterior jugular vein run? \
Inferiorly, near the midline to suprasternal region - penetrates investing layer of the deep cervical fascia. Passes deep to sternocleidomastoid to join external jugular in root of neck.
Anterior triangle is divided into 4 main triangles.
Muscular triangle
Carotid triangle
Submandibular triangle
Submental triangle
What are the borders of the muscular triangle?
Superolateral - superior belly of omohyoid muscle
Inferolateral - anterior border of sternocleidomastoid
Medial - median plane of neck.
List contents of muscular triangle/
Infrahyoid muscles - sternohyoid muscle, superior belly of omohyoid muscle, sternothyroid muscle and thyrohyoid muscle
thyroid gland
parathyroid glands
Sternohyoid? Innervation?
21 on image - sits in front.
Ansa cervicalis - C1-C3
depress hyoid bone
Superior belly of omohyoid muslce? Innervation? Sits lateral to?
C1
Sits lateral to sternohyoid muscle.
Action - depress the hyoid bone.
Sternothyroid muscle?
C1 - C3
and the sternothyroid depress the larynx.
Thyrohyoid muscle?
Eleveates larynx, depress hyoid bone.
Innervation: hypoglossal + C1
Boundaries of the carotid triangle?
Inferomedial - superior belly of omohyoid muscle.
Inferolateral - anterior border of sternocleidomastoid muscle.
Superior - posterior belly of diagastric muscle.
Contents of carotid triangle?
Carotid arteries: common, internal and external
Branches of external artery
hypoglossal nerve
branches of vagus.
Superior root of ansa cervicalis?
C2-C3
Inferior root ansa cervicalis?
C2, C3
What nerve passes through the thyrohyoid membrane?
Internal branch of superior laryngeal nerve
What does the internal branch of the superior laryngeal nerve supply?
Mucosa of the larynx with sensory fibres.
What does the external branch of superior laryngeal nerve do?
Supply cricothyroid muscle and its function is to tense the vocal cord by activating the cricothyroid muscle and increasing pitch.
Contents of carotid sheath?
Common carotid artery
Internal carotid artery
Internal jugular vein
Vagus
Where can the external carotid artery be found?
At superior horn of thyroid cartilage. passes on medial side, deep to posterior belly of diagastric.
6 branches of external carotid artery?
Ascending pharyngeal artery
Superior thyroid artery
Lingual artery
Facial artery
Occipital artery
Posterior auricular artery
Carotid sinus?
Dilation of origin of internal carotid artery
Carotid body - innervated by glossopharyngeal nerve
Monitors change in O2 and CO2
Identify vagus
Borders of the submandibular triangle.
Superior: inferior border of mandible
anteroinferior - anterior belly of diagastric muscle
Posteroinferior: posterior belly of diagastric muscle
Superficial (roof - investing layer of deep cervical fascia
Floor - mylohyoid and hypoglossus.
Contents of submandibular triangle?
Submandibular gland, facial artery, facial vein, stylohyoid muscle, hypoglossal nerve, lymph nodes.
Submandibular gland
Anterior belly diagastric innervation?
V3 - mylohyoid branch
3 on image
Posterior belly diagastric?
facial nerve
attaches to mastoid process of temporal bone.
anterior and posterior belly digastric attach to?
Intermediate tendon.
elevate hyoid bone, depress mandible.
Stylohyoid
10 on image styloid process to hyoid bone.
Innervated by facial nerve.
Mylohyoid
18 on image.
Innervated by V3 - mandicular nerve.
Boundaries of submental triangle
right and left: anterior bellies of right and left digastric muscles
Inferior - hyoid bone
Superficial - investing layer of deep cervical fascia
Deep (floor) - mylohyoid muscle.
Contains submental lymph nodes.
Mylohyoid innervation and action?
Support the floor of oral cavity
Mylohyoid nerve of V3
