Intrinsic Back Muscles (Superficial)

Question 1

What is the origin of splenius capitis?

Answer 1

Lower half of ligamentum nuchae
SPs of C7 - T3 or T4

Question 2

What is the insertion of splenius capitis ?

Answer 2

Mastoid process
Occipital bone below lateral 1/3 of superior nuchal line

Question 3

What are the bilateral and unilateral actions of splenius capitis?

Answer 3

Bilateral: extends head
Unilateral: ipsilaterally rotates head (same side)

Question 4

What is the blood supply of splenius capitis?

Where does this blood supply run?

Answer 4

Transverse cervical artery

Runs beneath trapezius and on top of splenius capitis

Branches from thyrocervical trunk (which branches from the first region of the subclavian artery)

Occipital artery
Branches from external carrotid

Question 5

What is the innervation of splenius capitis?

Answer 5

Cervical dorsal Rami C2, C3

Question 6

What is the origin of splenius cervicis?

Answer 6

SPs of T3 to T6
(Starts on last SP of splenius capitis origin and goes down Three segments)

Question 7

What is the insertion of splenius cervicis?

Answer 7

TPs C1 to C3

Question 8

What is the innervation of splenius cervicis?

Answer 8

Lower cervical dorsal rami

C4 and down

Question 9

What arteries supply splenius cervicis?

Answer 9

Occipital artery

Transverse cervical artery

Question 10

What is the action of splenius cervicis?

Answer 10

Unilaterally: ipsilaterally rotates cervical spine

Bilaterally: extends cervical spine

Question 11

What are the splenius muscles deep to?

Answer 11

Splenius capitis:
Deep to trapezius
Inferiorly deep to serratus posterior Superior (at lower end)

Splenius cervicis:
Superior portion: deep to splenius capitis
Inferior portion: deep to trapezius and serratus posterior superior