Neck muscle extensors

Question 1

Levator scapulae

Answer 1

Origin:
transverse processes of C1-C4

Insertion:
medial border of scapula

Action:

• elevates and medially rotates and retracts the scapula
• extends and laterally flexes the neck

Nerve supply:
ventral rami (C3,C4)
dorsal scapular nerve (C5)

Question 2

Splenius cervicis

Answer 2

Origin:
Upper spinous processes of T3-T6

Insertion:
transverse processes of C1-4

Direction:
upwards

Action:

• Bilateral action- neck extension
• unilateral action - ipsilateral lateral flexion and rotaion

Nerve supply:
Dorsal rami C5,6,7

Question 3

Splenius capitis

Answer 3

Origin:

• spinous processes (T2-C7)
• Lower half of ligamentum nuchae

Insertion:
Mastoid process and lateral 1/3 of superior nuchal line

Direction:
upwards

Action:

• Bilateral action - neck extension
• Unilateral action - ipsilateral lateral flexion and rotation.

Nerve supply:
Dorsal rami (C3,4,5,)

Question 4

Iliocostalis cervicis

Answer 4

Origin:
angles of third to sixth rib

Insertion:
posterior tubercles of transverse processes of C4-C6

Action:
extends and laterally flexes the vertebral column

Nerve supply:
dorsal rami

Question 5

Rectus capitis posterior major

Answer 5

Origin:
C2

Insertion:
the skull

Action:

• ipsilateral- roation
• bilateral- extends head on neck

Nerve supply:
dorsal rami of C1

Question 6

Obliquus capitis superior

Answer 6

Origin:
C1 transverse processes

Insertion:
the skull

Action:

• ipsilateral- rotation
• bilateral- extends head on neck

Nerve supply:
Dorsal rami C1

Question 7

Longissimus cervicis

Answer 7

Origin:
transverse processes of T1-T6

Insertion:
Posterior tuberckes of transverse processes of C2-C6

Action:

• unilateral action- ipsilateral side flexion/rotation
• bilateral action - trunk/neck extension

Nerve supply:
adjacent posterior primary rami

Question 8

spinalis cervicis

Answer 8

Origin:
spinous process to spinous process

Direction:
Upwards

Action:

• unilateral action- ipsilateral side flexion/rotation
• bilateral action- trunk extesion

Nerve supply:
adjacent posterior primary rami

Question 9

Rectus capitus posterior minor

Answer 9

Origin:
C1

Insertion:
The skull

Action:

• ipsilateral action- rotation
• bilateral action- extends head on neck

Nerve supply:
Dorsal rami (C1)