OIA of Anterior and Posterior Trunk Muscles

Question 1

origin of external oblique

Answer 1

• fleshy strips from outer surface of lower 8 ribs

Question 2

insertion of external oblique

Answer 2

• linea alba via broad aponeurosis
• pubic crest
• pubic tubercle
• iliac crest

Question 3

origin of internal oblique

Answer 3

• lumbar fascia
• iliac crest
• inguinal ligament

Question 4

insertion of internal oblique

Answer 4

• linea alba
• pubic crest
• last 3/4 rubs and costal margin

Question 5

what do the internal, transversus and external oblique have in common?

Answer 5

they all insert into the linea alba and pubic crest

Question 6

origin of transversus abdominis

Answer 6

• inguinal ligament
• lumbar fascia
• cartilages of last 6 ribs
• iliac crest

Question 7

insertion of transversus abdominis

Answer 7

• linea alba
• pubic crest

Question 8

origin of rectus abdominis

Answer 8

• pubic crest and pubic symphisis

Question 9

insertion of rectus abdominis

Answer 9

• xiphoid process
• costal cartilage of ribs 5-7

Question 10

origin of external intercostals

Answer 10

• inferior border of rib above

Question 11

insertion of external intercostals

Answer 11

• superior border of rib below

Question 12

origin of internal intercostals

Answer 12

• superior border of rib below

Question 13

insertion of internal intercostals

Answer 13

• inferior border (costal groove) of rib below

Question 14

origin of diaphragm

Answer 14

• inferior interal surface of rib cage + sternum
• costal cartiliages of last six ribs
• lumbar vertebrae

Question 15

insertion of diaphragm

Answer 15

• central tendon

Question 16

origin of scalenes

Answer 16

• transverse processes of cervical vertebrae

Question 17

insertion of scalenes

Answer 17

• anterolaterally on first two ribs

Question 18

origin of iliocostalis

Answer 18

• iliac crests
• inferior 6 ribs
• ribs 3-6

Question 19

insertion of iliocostalis

Answer 19

• angles of ribs
• transverse processes of C4-C6

Question 19

origin of longissimus

Answer 19

• transverse processes of lumbal and cervical vertebrae

Question 20

insertion of longissimus

Answer 20

• transverse processes of thoracic or cervical vertebrae and to ribs superior to origin
• capitis inserts into mastoid process

Question 21

origin of spinalis

Answer 21

• spines of upper lumbar and lower thoracic vertebrae

Question 22

insertion of spinalis

Answer 22

• spines of upper thoracic and cervical vertebrae

Question 23

origin of semispinalis

Answer 23

• transverse process of C7-T12

Question 24

insertion of semispinalis

Answer 24

- occipital bone - spinous process of cervical and thoracic (T1-T4) vertebrae

Question 25

origin of quadratus lumborum

Answer 25

- iliac crest - lumbar fascia

Question 26

insertion of quadratus lumborum

Answer 26

- transverse processes of upper lumbar vertebrae - lower margin of 12th rib

Question 27

what muscles all support pelvic organs?

Answer 27

coccygeus, deep transverse perineal muscles, levator ani, external urethral sphinter