Origins, insertions + actions of back muscles

Question 1

Quadratus lumborum

Answer 1

Origin: 12th rib.
Insertion: Iliac crest.
Actions: Extends + laterally flexes lumbar spine + aid breathing.

Question 2

Rotatores

Answer 2

Origin: Transverse processes of thoracic vertebrae.
Insertion: Spinous processes of 2 thoracic vertebrae above.
Action: Extension + Rotation.

Question 3

Multifidus

Answer 3

Origin + insertion: Spans the length of vertebral column
Action: Extends neck + spine.

Question 4

Semispinalis

Answer 4

Origin: Thorax.
Insertion: Head
Action: Extends + Rotates.

Question 5

Intertransverasrri

Answer 5

Origin: Transverse process L1-L4.
Insertion: Transverse processes L2-L5.
Action: Lateral flexion.

Question 6

Interspinalis

Answer 6

Origin: Spinous processes L2-L5.
Insertion: Spinous processes L1-L4.
Action: Extension.

Question 7

Spinalis

Answer 7

Origin + insertion: Spinous process to spinous process.
Action: Extends + laterally flexion.

Question 8

Longissimus

Answer 8

Origin + insertion: Transverse process to Transverse process.
Action: Extends + laterally rotates.

Question 9

Iliocostalis

Answer 9

Origin + insertion: Angles of rib to angle of rib.
Action: Extends + laterally rotates.

Question 10

Serratus posterior superior

Answer 10

Origin: Nuchal ligament.
Insertion: 2nd to 5th ribs.
Action: Elevates ribs.

Question 11

Serratus posterior inferior

Answer 11

Origin: Spinous process T11 - L2.
Insertion: 9th to 12th ribs.
Action: Depresses ribs.