Neck Muscles

Question 1

Semispinalis Capitis

Answer 1

Origin: articular processes of inferior cervical & transverse process of superior thoracic vertebrae

Insertion: occipital bone

Action: -Bilateral extend head
-Unilateral laterally flexes neck to same side

Innervation: spinal nerve

Question 2

Sternocleidomastoid

Answer 2

Origin: sternal end of clavicle and manubrium

Insertion: mastoid region of skull

Action: -Bilateral: neck flexion
-Unilateral: turns face to opposite side

Innervation: accessory nerve (CN XI)

Question 3

Splenius Capitis

Answer 3

Origin: spinous process/ligaments of inferior cervical vertebrae

Insertion: mastoid process, occipital bone of skull

Action: -Bilateral extend head
-Unilateral laterally flexes neck to same side

Innervation: cervical spinal nerves

Question 4

Longissimus cervicis

Answer 4

Origin: transverse processes of superior thoracic vertebrae

Insertion: transverse process of middle and superior cervical vertebrae

Action: -Bilateral extend head
-Unilateral laterally flexes neck to same side

Innervation: cervical and thoracic spinal nerves

Question 5

Longissimus thoracis

Answer 5

Origin: transverse process of all thoracic and lumbar vertebrae

Insertion: transverse processes of all thoracic vertebrae

Action: -Bilateral:extension of spine
-Unilaterally: lateral flexion of spine

Innervation: thoracic and lumbar spinal nerves

Question 6

Thyrohyoid

Answer 6

ORIGIN: thyroid cartilage of larynx

INSERTION: hyoid bone

ACTION: elevates thyroid, depresses hyoid bone

INNERVATION: hypoglossal nerve

Question 7

Scalenes (anterior, middle, posterior)

Answer 7

ORIIGIN: transverse processes of C2- C7

INSERTION: Ribs 1 & 2

ACTION: elevates ribs 1 & 2

INNERVATION: cervical spinal nerves