Anterior Triangle Of The Neck Flashcards
What are the borders of the anterior triangle?
Midline of the neck, SCM and lower border of the mandible
What are the sub-triangles of the anterior triangle?
Carotid, submandibular, muscular and submental
What are the borders for the carotid triangle?
SCM, superior belly of omohyoid and posterior belly of the digastric
What are the borders for the submandibular triangle?
Anterior and posterior bellies of digastric and the mandible
What are the borders for the muscular triangle?
SCM, superior belly of omohyoid and midline from hyoid to manubrium
What are the borders for the submental triangle?
Unpaired
Both anterior bellies of digastric and hyoid bone
What are the contents of the submandibular (digastric) triangle?
Submandibular gland and LNs Hypoglossal nerve (CN XII), mylohyoid nerve, parts of facial artery and vein
What are the contents of the submental triangle?
Submental LNs and small veins that unite to form the anterior jugular vein
What are the contents of the carotid triangle?
Carotid sheath containing common carotid A and its branches
Internal jugular vein and its tributaries, vagus nerve, external carotid A and some branches, hypoglossal nerve (CN XII) and superior root of the Ansa cervicalis
Spinal accessory nerve (CN XI), thyroid gland, larynx and pharynx, deep cervical LNs and branches of the cervical plexus
What are the contents of the muscular triangle?
Sternothyroid and sternohyoid muscles
Thyroid and parathyroid glands
Which muscles are in the suprahyoid region?
Mylohyoid and geniohyoid
Which muscles are in the digastric suprahyoid region?
Digastric, hyoglossal and stylohyoid muscles
Which muscles are infrahyoid?
Sternohyoid, omohyoid, sternothyroid, thyrohyoid and cricothyroid
What is the origin and insertion of the mylohyoid?
Origin: mylohyoid line on mandible
Insertion: body of hyoid
What is the action of the mylohyoid?
Elevates hyoid bone, floor of mouth and tongue
Supports tongue and hyoid bone during swallowing, speaking and in tongue protrusion
Which muscles are innervated by the nerve to mylohyoid (branch of inferior alveolar N from CN V3)?
Mylohyoid and anterior belly of digastric
What is the origin and insertion of the geniohyoid muscle?
Origin: mental spine on the mandible
Insertion: body of hyoid bone
Located superior/deep to the mylohyoid
What is the action of the geniohyoid muscle?
Elevates hyoid bone, shortens floor fo the mouth and widens pharynx
Which two muscles are innervated by C1 via the hypoglossal N?
Geniohyoid (suprahyoid M) and thyrohyoid (infrahyoid)
What is the origin and insertion for the digastric muscle?
Origin: digastric fossa of the mandible (anterior belly) and mastoid notch of the temporal bone (posterior belly)
Insertion: intermediate tendon on body and greater horn of hyoid
What is the action of the digastric muscle?
Elevates and steadies the hyoid bone during swallowing and speaking
Depresses the mandible
Which muscles are innervated by the facial N?
Posterior belly of the digastric and stylohyoid M
What is the action of the stylohyoid muscle?
Elevates and retracts hyoid bone
Elongates floor of the mouth
Which muscles are innervated by the Ansa cervicalis (C1-3)?
Most infrahyoid muscles including sternohyoid, sternothyroid (C2-3) and omohyoid
Which infrahyoid muscles depress the hyoid?
Sternohyoid, thyrohyoid and omohyoid
Which infrahyoid muscles depresses thyroid cartilage?
Sternothyroid
Which infrahyoid muscle elevates thyroid cartilage?
Thyrohyoid
Which infrahyoid muscle retracts the hyoid?
Omohyoid
What is the origin and insertion of the hyoglossus muscle?
From hyoid bone to lateral tongue
What is the action of the hyoglossus muscle?
Depresses and shortens the tongue
What is the hyoglossus muscle innervated by?
Cn XII (hypoglossal N)
The cricothyroid muscle is important for what?
Vocalization
What innervates the cricothyroid muscle?
External laryngeal N from the vagus N
