anatomy of trunk

Question 1

What is the action, origin, insertion of platisma

Answer 1

A: tenses skin of neck and depresses mandible
O: clavicle
I: mandible

Question 2

What is the action, origin, insertion of sternoclavicular mastoid

Answer 2

neck flexion, lateral cervical flexion, cervical rotation
O: sternal head: sternum, clavicular head: clavicle
I: mastoid process

Question 3

What is the action, origin, insertion of scalenes

Answer 3

A: assists with breathing, lateral flexion, if bs activated forward neck flexion
cervical rotation
contralateral muscles moves head
O: 1st + 2nd ribs
I: prosthesis of cervical spine

Question 4

What is the action, origin, insertion of splenius capitis and cervices

Answer 4

A: both contract = head hyperextension
lat extension and lat rotation ipsilaterally
O: vertebrae C7-T3 for capitis and T3-T6 for cervices
I: lateral superior occipital bone = capitis, C1-C3 vertebrae = cervices

Question 5

What is the action of the semispinalis muscles

Answer 5

A: bilat contraction = head cervical and thoracic spine extension
unilateral = ipsilateral flexion of cervical / thoracic spine

Question 6

What is the origin and insertion of the semispinalis muscles?

Answer 6

Capitis O: C7-T4 I: occipital bone
Cervicis O: C7-T1 nuchal ligament, I: C2-C4
Thoracis O: T11-L2 I: T2-T8

Question 7

What is the action, origin, insertion of external obliques?

Answer 7

A: Rotates body to opposite side
lateral flexion
both sides creates trunk flexion
O: side of ribs - centre thoracic
I: iliac crest

Question 8

What is the action, origin, insertion of internal obliques?

Answer 8

A: lateral flexion
both sides = trunk flexion
Ipsilateral for rotation
O: iliac crest
I: lumbar region fasciae

Question 9

What is the action, origin, insertion of rectus abdomini?

Answer 9

A: main role is trunk flexion
also used for expiration
O: pubic crest and pubic symphysis
I: xiphoid process, costal cartilage ribs 5-7

Question 10

What is the action, origin, insertion of transverse abdomini?

Answer 10

A: maintain spine curve and stabilise trunk
O: ribs
I: middle thoracic lumbar region

Question 11

What is the action, origin, insertion of erector spini?

Answer 11

Spinals, longissimus, ilis, costalis
Keep spine straight
neck trunk extesnors
thoracic or lumbar
long muscles

Question 12

What is the action, origin, insertion of multifidis

Answer 12

spine stabiliser and for small movements
attach direct to spinal column

Question 13

What is the action, origin, insertion quadratus lumborum

Answer 13

A: pelvis stability
O: posterior iliac crest
I: inferior 12th rib and transverse processes, 1,2 and 4th lumbar