Trunk Muscles

Question 1

Erector Spinae: Iliocostalis (Lumborum)

Answer 1

Origin: sacrum & iliac crest
Insertion: rib 8-12
Action: Extension of spine & head, stabilization of the thrunk, lateral flexion of the spine
Innervation: Dorsal Rami Spinal Nerve

Question 2

Erector Spinae: Iliocostalis (Thoracis)

Answer 2

Origin: ribs 8-12
Insertion: rib 1-7
Action: Extension of spine & head, stabilization of the thrunk, lateral flexion of the spine
Innervation: Dorsal Rami Spinal Nerve

Question 3

Erector Spinae: Iliocostalis (Cervicis)

Answer 3

Origin: rib 3-7
Insertion: Transverse processes C3-C6
Action: Extension of spine & head, stabilization of the thrunk, lateral flexion of the spine
Innervation: Dorsal Rami Spinal Nerve

Question 4

Erector Spinae: Longissimus (Thoracis)

Answer 4

Origin: sacrum & TPs L1-L5
Insertion: TPs T1-T12 & rib 1-12
Action: Extension of spine & head, stabilization of the thrunk, lateral flexion of spine
Innervation: Dorsal Rami Spinal Nerve

Question 5

Erector Spinae: Longissimus (Cervicis)

Answer 5

Origin: TPs of T1-T5
Insertion: TPs of C2-C6
Action: Extension of spine & head, stabilization of the thrunk, lateral flexion of spine
Innervation: Dorsal Rami Spinal Nerve

Question 6

Erector Spinae: Longissimus (Capitis)

Answer 6

Origin: TPs of C6-T3
Insertion: mastoid process
Action: Extension of spine & head, stabilization of the thrunk, lateral flexion of spine
Innervation: Dorsal Rami Spinal Nerve

Question 7

Erector Spinae: Spinalis (Thoracis)

Answer 7

Origin: SPs T10-L2
Insertion: SPs T3-T9
Action: Extension of head & spine, stabilization of the trunk, lateral flexion of spine

Question 8

Erector Spinae: Spinalis (cervicis)

Answer 8

Origin: SPs C6-C7
Insertion: SPs C2-C3
Action: Extension of head & spine, stabilization of the trunk, lateral flexion of spine

Question 9

Erector Spinae: Spinalis (capitis)

Answer 9

Origin: C7-T2
Insertion: occipital bone
Action: Extension of head & spine, stabilization of the trunk, lateral flexion of spine

Question 10

Quadratus Lumborum

Answer 10

Origin: Iliac crest
Insertion: Rib 12 & L1-L4
Action: elevation of pelvis, lateral flexion of the trunk, extension of the lumbosacral spine
Innervation: Lumbar Plexus

Question 11

Serratus Posterior Superior

Answer 11

Origin: SPs C7-T3
Insertion: Rib 2-5
Action: Elevates the ribs
Innervation: 2nd, 3rd, 4th, 5th intercostal nerves

Question 12

Serratus Posterior Inferior

Answer 12

Origin: SPs T11-L2
Insertion: Rib 9-12
Action: Pulls the ribs downwards and backwards
Innervation: Intercostal nerves

Question 13

Transversospinalis: Semispinalis (thoracis)

Answer 13

Origin: TPs ot T6-T12
Insertion: SPs of C6-T4
Action: Extension of head & neck, controls lateral flexion to opposite side, maintains head posture
Innervation: Dorsal Rami Spinal Nerve

Question 14

Transversospinalis: Semispinalis (cervicis)

Answer 14

Origin: TPs of T1-T5
Insertion: SPs of C2-C5
Action: Extension of head & neck, controls lateral flexion to opposite side, maintains head posture
Innervation: Dorsal Rami Spinal Nerve

Question 15

Transversospinalis: Semispinalis (capitis)

Answer 15

Origin: TPs C7-T6 & APs of C4-C6
Insertion: occipital bone
Action: Extension of head & neck, controls lateral flexion to opposite side, maintains head posture
Innervation: Dorsal Rami Spinal Nerve

Question 16

Transversospinalis: Multifidi (lumborum)

Answer 16

Origin: mammillary processes of L1-L5
Insertion: SPs of L5-C2
Action: Extension of trunk & neck, rotate spine to opposite side, control lateral flexion
Innervation: Dorsal Rami Spinal Nerve

Question 17

Transversospinalis: Multifidi (thoracis)

Answer 17

Origin: TPs T1-T12
Insertion: SPs of L5-C2
Action: Extension of trunk & neck, rotate spine to opposite side, control lateral flexion
Innervation: Dorsal Rami Spinal Nerve

Question 18

Transversospinalis: Multifidi (cervicis)

Answer 18

Origin: APs of C4-C7
Insertion: SPs of L5-C2
Action: Extension of trunk & neck, rotate spine to opposite side, control lateral flexion
Innervation: Dorsal Rami Spinal Nerve