Anterior Neck Muscles

Question 1

Sternocleidomastoid Action

Answer 1

uni: ipsilateral lateral flexion, contralateral rotation
bi: extension of neck at OA joint, flexion of cervical vertebrae, or extension of superior cervical vertebrae while flexing inferior vertebrae
*w/ cervical vertebrae fixed, may elevate manubrium and medial clavicle

Question 2

Sternocleidomastoid SMA

Answer 2

mastoid process, superior nuchal line

Question 3

Sternocleidomastoid ILA

Answer 3

sternal head: manubrium of sternum
clavicular head: medial third of clavicle

Question 4

Sternocleidomastoid Innervation

Answer 4

spinal accesory nerve (CN XI), C3 and C4 (pain and proprioception)

Question 5

Platysma Purposeful Activity

Answer 5

facial expression

Question 6

Platysma Innervation

Answer 6

facial nerve (CN VII)

Question 7

Suprahyoids

Answer 7

• mylohyoid
• digastric (anterior belly, posterior belly)
• stylohyoid
• geniohyoid

Question 8

Infrahyoids

Answer 8

• thyrohyoid
• sternothyroid
• omohyoid
• sternohyoid

Question 9

Prevertebral Neck Muscles

Answer 9

• rectus capitis anterior
• longus capitis
• longus colli

Question 10

Prevertebral Neck Muscles Action

Answer 10

• rectus capitis anterior & longus capitis: anterior tilt (slight flexion) of OA joint
• can be damaged by whiplash