Anterolateral neck muscles

Question 1

Anterior digastric

Answer 1

Attachments: from the digastric fossa of the mandible to the intermediate tendon (greater cornu of hyoid)

Function: depression of the mandible or elevation of the hyoid

Innervation: mylohyoid branch of the inferior alveolar n.

Blood supply: submental branch of the facial a.

Question 2

Posterior digastric

Answer 2

Attachments: from the temporal mastoid notch to the intermediate tendon (greater cornu of hyoid)

Function: depression of the mandible or elevation of the hyoid

Innervation: facial n.

Blood supply: occipital & posterior auricular a.

Question 3

Geniohyoid

Answer 3

Attachments: from the inferior genial tubercle of the mandible to the anterior aspect of the body of the hyoid

Function: elevation & anterior displacement of the hyoid, or depression of the mandible with a fixed hyoid

Innervation: ventral ramus of C1 (via the hypoglossal n.)

Blood supply: sublingual a.

Question 4

Longus capitis

Answer 4

Attachments: from the anterior tubercles of the transverse processes of cervical vertebrae to the basilar occipital bone

Function: flexion of the head & neck

Innervation: ventral rami of cervical spinal n.

Blood supply: vertebral, ascending cervical, ascending pharyngeal & inferior thyroid a.

Question 5

Longus colli (L. neck)

Answer 5

Attachments: from cervical vertebral bodies to cervical vertebral bodies & transverse processes

Function: flexion of the neck

Innervation: ventral rami of cervical spinal n.

Blood supply: vertebral, ascending pharyngeal & inferior thyroid a.

Question 6

Mylohyoid

Answer 6

Attachments: from the mylohyoid line of the mandible to the midline raphe & anterior aspect of body of the hyoid

Function: elevation of the floor of the oral cavity

Innervation: mylohyoid branch of the inferior alveolar n.

Blood supply: submental branch of facial & lingual a.

Question 7

Omohyoid (G. omos, shoulder)

Answer 7

Attachments: from the superior border of the scapula medial to the scapular notch to the lateral aspect of the hyoid passing through an intermediate tendon sling loosely associated with the clavicle & 1^st rib

Function: depression of the hyoid

Innervation: ansa cervicalis

Blood supply: superior thyroid & suprascapular a.

Question 8

Scalenus anterior

Answer 8

Attachments: from the transverse process of the middle cervical vertebrae to the scalene tubercle of the 1^st rib

Function: elevation of the 1^st rib (during forced inspiration) & flexion & rotation of the neck

Innervation: ventral rami of cervical spinal n.

Blood supply: ascending cervical, suprascapular & transverse cervical a.

Question 9

Scalenus medius

Answer 9

Attachments: from the transverse processes of cervical vertebrae to 1^st rib

Function: elevation of 1^st rib (during forced inspiration)

Innervation: ventral rami of cervical spinal n.

Blood supply: ascending cervical, suprascapular & transverse cervical a.

Question 10

Scalenus posterior

Answer 10

Attachments: from lower cervical transverse processes to the 2^nd rib

Function: elevation of the rib (during forced inspiration)

Innervation: ventral rami of cervical spinal n.

Blood supply: ascending cervical, suprascapular & transverse cervical a.

Question 11

Sternocleidomastoid

Answer 11

Attachments: from the lateral aspect of the mastoid process & superior nuchal line to the manubrium & medial 1/3^rd of the clavicle

Function: flexion of the head & neck, & contralateral rotation of the head

Innervation: accessory n.

Blood supply: occipital, posterior auricular, superior thyroid & suprascapular a.

Question 12

Sternohyoid

Answer 12

Attachments: from the posterior side of the proximal clavical & adjacent manubrium to the inferior border of body of the hyoid

Function: depresses the hyoid

Innervation: ansa cervicalis

Blood supply: superior thyroid

Question 13

Sternothyroid

Answer 13

Attachments: from the posterior aspect of the manubrium to the thyroid lamina

Function: depression of the elevated larynx

Innervation: ansa cervicalis

Blood supply: superior thyroid a.

Question 14

Stylohyoid

Answer 14

Attachments: from the styloid process to the greater cornu of the hyoid

Function: elevation & retraction of the hyoid

Innervation: facial n.

Blood supply: occipital, posterior auricular & facial a.

Question 15

Thyrohyoid

Answer 15

Attachments: from the thyroid lamina to the hyoid bone

Function: depression of the hyoid or elevation of the thyroid cartilage

Innervation: ventral ramus of C1 via the hypoglossal n.

Blood supply: superior thryroid a.