Muscles of Anterior Neck

Question 1

Function of the Sternocleidomastoid Muscle

Answer 1

• Ipsilateral neck flexion and contralateral rotation when unilaterally contracted
• Neck flexion when bilaterally contracted

Question 2

Innervation of the Sternocleidomastoid muscle

Answer 2

Accessory Nerve (CN XI)

Question 3

Blood supply of the Sternocleidomastoid muscle

Answer 3

Superior thyroid artery and occipital arteries

Question 4

Function of the Platysma Muscle

Answer 4

Tighten skin over the neck and draws corners of the mouth

Question 5

Innervation of the platysma Muscle

Answer 5

Cervical branch of the facial nerve (CN VII)

Question 6

Blood supply of the platysma muscle

Answer 6

Submental cranch of the facial artery and suprascapular artery

Question 7

Innervation of the Sternohyoid muscle

Answer 7

ansa cervicalis of the cervical plexus receiving fibers from the ventral rami of C1-C3 spinal nerves

Question 8

Innervation of the Omohyoid muscle

Answer 8

ansa cervicalis of the cervical plexus receiving fibers from the ventral rami of C1-C3 spinal nerves

Question 9

Innervation of the Sternothyroid muscle

Answer 9

ansa cervicalis of the cervical plexus receiving fibers from the ventral rami of C1-C3 spinal nerves

Question 10

Innervation of the Thyrohyoid Muscle

Answer 10

ansa cervicalis of the cervical plexus receiving fibers from the ventral rami of C1-C3 spinal nerves

Question 11

The function of the Sternohyoid and Omohyoid muscle

Answer 11

Depresses the hyoid bone

Question 12

Function of the Sternothyroid Muscle

Answer 12

Depresses thyroid cartilage

Question 13

Innervation of the Infrahyoid muscles

Answer 13

infrahyoid muscles (aka strap muscles): Sternohyoid, Omohyoid, Sternthyroid, and Thyrohyoid muscles

ansa cervicalis of the cervical plexus receiving fibers from the ventral rami of C1-C3 spinal nerves

Question 14

Function of Thyrohyoid muscle

Answer 14

Elevates the thyroid cartilage and depressed the hyoid bone

Question 15

Blood supply of the Infrahyoid Muscles

Answer 15

Infrahyoid muscles (aka strap muscles): Sternohyoid, Omohyoid, Thyrohyoid, and Sternothyroid muscles

Supplied by the Superior Thyroid Artery

Question 16

Function of Anterior and Posterior Belly of Digastric muscles

Answer 16

Anterior belly contraction: Depresses the mandible

Posterior belly contraction: Elevate the hyoid bone during chewing and swallowing

Question 17

Innervation of the Anterior and Posterior bellies of the Digastric muscle

Answer 17

Anterior belly: Mylohyoid nerve (CNV3)

Posterior Belly: Digastric branch of Facial Nerve (CN VII)

Question 18

Blood supply of the Anterior and Posterior belly of Digastric muscles

Answer 18

Facial artery and occipital artery

Question 19

Function of the Stylohyoid muscle

Answer 19

Elevates and retracts the hyoid bone

Question 20

Innervation of the stylohyoid muscle

Answer 20

Stylohyoid branch of the facial nerve (CN VII)

Question 21

Blood supply of the Stylohyoid muscle

Answer 21

Branched of the external carotid artery

(lingual artery, facial artery, occipital artery, posterior auricular artery)

Question 22

Function of the mylohyoid muscle

Answer 22

Raise the floor of oral cavity, elevate hyoid bone, elevate the tongue, and depress mandible

Question 23

Innervation of the mylohyoid muscle

Answer 23

Mylohyoid nerve (CNV3)

Question 24

Blood supply of the mylohyoid Muscles

Answer 24

Mylohyoid artery of inferior alveolar artery and submental artery of facial artery

Question 25

Function of the Geniohyoid muscle

Answer 25

Elevate the hyoid bone and tongue during swallowing

Question 26

Innervation of the Geniohyoid muscle

Answer 26

Ansa cervical (C1)

Question 27

Blood supply of the Geniohyoid muscle

Answer 27

Lingual artery

Question 28

Function of the Cricothyroid muscles

Answer 28

Tenses and elongates the vocal sords

Question 29

Innervation of the Cricothyroid muscle

Answer 29

External branch of superior laryngeal nerve

Question 30

Blood supply of the Cricothyroid muscle

Answer 30

Branch of the superior thyroid artery

Question 31

Spinal Accessory Nerve (CN XI)

Answer 31

Origin: C1-C6 ventral roots (reenters the cranial cavity via foramen magnum and exits via jugular foramen and innervates the muscles)

Innervates: SCM and Trapezius

Question 32

Phrenic Nerve

Answer 32

Origin: C3-C5 Ventral root (“C3, 4, 5 Keep the Diaphragm alive”)

Innervated the Diaphragm

Question 33

Hypoglossal Nerve (CN XII)

Answer 33

Origin: Comes from the hypoglossal canal. Medulla

Innervates the intrinsic and extrinsic muscles of the tongue

Question 34

Ansa Cervicalis

Answer 34

Origin: C1-C3 ventral root

Innervated the Infrahyoid muscles (Sternohyoid, Sternothyroid, Thyrohyoid, Omohyoid muscles)

Question 35

Vagus Nerve (CN X)

Answer 35

Origin: Medulla

Motor: levator veli palatini, pharyngeal constrictors, intrinsic and extrinsic laryngeal muscles, and palatoglossus muscle

Sensory: inferior pharynx, larynx, thoracic and abdominal viscera

Parasympathetic: Thoracic and Abdominal viscera

Special sensory: epiglottis taste buds

Question 36

Right and Left recurrent laryngeal nerve

Answer 36

Motor: Intrinsic muscles of the larynx

Sensory: Larynx below vocal cords

Question 37

Superior laryngeal nerve

Answer 37

Internal laryngeal nerve

• Sensory to larynx above vocal cords

External laryngeal nerve

• Motor to cricothyroid muscle