Muscles of the Spine

Question 1

Serratus Posterior Superior

Answer 1

O : Spinous Processes of C7-T3 and the lower nuchal ligament
I : Superior border and external surfaces of rubs 2-5
A : Elevates ribs 205 at the sternocostal and costospinal joints

Question 2

Serratus Posterior Inferior

Answer 2

O : Spinous processes of T11-L2
I : Inferior borders and external surfaces of ribs 9-12
A : Depresses ribs 9-12 at sternocostal and costospinal joints

Question 3

Splenius Capitis

Answer 3

O : Nuchal ligament from C3-C6 and spinous processes of C7-T4
I : Mastoid process and lateral 1/3 of the superior nuchal line
A :
1. Extends the head and neck at the spinal joints
2. Laterally flexes the head and neck at the spinal joints
3. Ipsilaterally rotates the head and neck at the spinal joints

Question 4

Splenius Cervicis

Answer 4

O : Spinous processes of T3-T6
I : Posterior tubercles of transverse processes of C1-C3

Question 5

Interspinales Cervical

Answer 5

6 pairs between T1-C2

Question 5

Interspinales Thoracic

Answer 5

2 pairs between T2-T1 and T12-T11

Question 6

Interspinales Lumbar

Answer 6

4 pairs between L5-L

Question 7

Quadratus Lumborum

Answer 7

O : Medial 1/2 of inferior border of the 12th rib and TVP of L1-L4
I : Posteromedial iliac crest and iliolumbar ligament
SMA :
1. Elevates the same side pelvis at lumbosacral joint
2. Laterally flexes the lower lumbar spine relative to the upper lumbar spine at the spinal joints
3. Anterior tilts the pelvis at the lumbosacral joint and extends the lower lumbar spine relative to the upper lumbar spine at the spinal joints
RMA :
1. Laterally flexes the trunk at the spinal joints
2. Extend the trunk at the spinal joints
3. Depresses the 12th rib at the costospinal joints