thorax mm

Question 1

external intercostals

Answer 1

O: lower border of rib
I: upper border of rib below
A: elevate ribs during inspiration
I: intercostal nerves

Question 2

internal intercostals

Answer 2

O: inner surface of a rib and costal cartilages
I: upper borders of adj ribs below
A: draw ribs downward during forced expiration
I: intercostal nerves

Question 3

transversus thoracis

Answer 3

O: Inner surfaces of the lower
third of the body of the
sternum and adjacent
surfaces of the xiphoid
process
I: Internal surfaces of the sternocostal
joints associated with the second (or
third) through the sixth ribs
A: depresses ribs
I: intercostal nerves

Question 4

quadratus lumborum

Answer 4

O: Iliolumbar ligament and
crest of the ilium
I: Rib 12 and tips of the transverse
processes of the L1 to L4
A: Extension and side flexion of lumbar
spine, expiration
I: Ventral ramus of spinal
nerve roots T12-L3

Question 5

psoas major

Answer 5

O: Transverse processes and
lateral bodies of the T12-L4 including the
intervertebral discs
I: lesser trochanter of femur
A: Forward flexion and side flexion of
lumbar spine, Flexion of the hip joint
I: branches of ventral rami L1-L3

Question 6

Iliacus

Answer 6

O: Superior two thirds of the
iliac fossa, inner lip of the
iliac crest
I: lesser trochanter of femur
A: flexion of hip joint
I: femoral

Question 7

rectus abdominus

Answer 7

O: pubic crest and anterior pubic ligament
I: xiphoid process, 5-7 costal cartilages
A: expiration, flexion of spine
I: lower six or seven thoracic nerves

Question 8

external oblique

Answer 8

O: lateral side of ribs 4-12
I: iliac crest, linea alba, and contralateral rectus sheaths
A:
bilaterally: flexion of trunk and PPT of pelvis
unilaterally: lateral flexion and contralateral rotation of trunk
I: lower 6 thoracic nerves

Question 9

internal oblique

Answer 9

O: Iliac crest, inguinal
ligament, and
thoracolumbar fascia
I: Ribs 9-12, linea alba
A:
Unilaterally: lateral flexion and
ipsilateral rotation of the trunk
Bilaterally: flexion of the trunk and
posterior tilt of the pelvis
I: Lower six thoracic
nerves and the first
lumbar nerve

Question 10

transversus abdominus

Answer 10

O: Iliac crest, thoracolumbar
fascia, inner surface of the
cartilages of ribs 6-12 and
the inguinal ligament
I: linea alba
A: Bilaterally: stabilization of attachment
sites for other abdominal muscles;
compression of the abdominal cavity
I: Lower six thoracic
nerves and the first
lumbar nerve