Anterior and Posterior Wall

Question 1

Diaphragm

Answer 1

PROX. ATTACHMENT
Lumbar vertebra

DISTAL ATTACHMENT
Costal cartilages, xiphoid

ACTION
Inspiration, it flattens
Expiration, passively relaxes

INNERVATION
Phrenic nn (C3—C5) (mainly) and lower intercostal nn (secondarily)

Question 2

Psoas Major

Answer 2

PROX. ATTACHMENT
Bodies, Transverse processes, IVDs L1-L5

DISTAL ATTACHMENT
Lesser trochanter

ACTION
Flexion

ON WHICH BONE/JOINT
Thigh (Femur; Hip joit)

INNERVATION
Ventral rami L2-L4 (essentially femoral nerve)

Question 3

Iliacus

Answer 3

PROX. ATTACHMENT
Iliac fossa

DISTAL ATTACHMENT
Lesser trochanter

ACTION
Flexion

ON WHICH BONE/JOINT
Thigh (Femur; Hip joit)

INNERVATION
Femoral

Question 4

Quadratus Lumborum

Answer 4

PROX. ATTACHMENT
Rib 12; Lumbar transverse processes

DISTAL ATTACHMENT
Iliac crest

ACTION
Unilateral: Lateral flexion
Bilateral: Extension

ON WHICH BONE/JOINT
Trunk (Vertebral column)

INNERVATION
Ventral rami T12-L4

Question 5

Rectus Abdominis

Answer 5

FIBER DIRECTION
N/A

PROXIMAL ATTACHMENT
Xiphoid; Lower costal cartilages

DISTAL ATTACHMENT
Pubic symphysis; Pubic crest

ACTION
Flex trunk

INNERVATION
Ventral rami

Question 6

External Abdominal Oblique

Answer 6

FIBER DIRECTION
Anteroinferior; Hands in same pocket

PROXIMAL ATTACHMENT
Ribs 5-12; Iliac crest

DISTAL ATTACHMENT
Linea alba; Pubic tubercle

ACTION
(Bilateral: Compress abdominal contents)
Bilateral: Flex trunk
Unilateral: Rotate trunk (contralateral)
Unilateral: Lateral flex trunk (ipsilateral)

INNERVATION
Ventral rami

Question 7

Internal Abdominal Oblique

Answer 7

FIBER DIRECTION
Posteroinferior; Hands in opposite pocket

PROXIMAL ATTACHMENT
Thoracolumbar fascia; Ribs 10-12; Iliac crest

DISTAL ATTACHMENT
Linea alba; Pubic tubercle

ACTION
(Bilateral: Compress abdominal contents)
Bilateral: Flex trunk
Unilateral: Rotate trunk (contralateral)
Unilateral: Lateral flex trunk (ipsilateral)

INNERVATION
Ventral rami

Question 8

Transversus Abdominis

Answer 8

FIBER DIRECTION
Horizontal

PROXIMAL ATTACHMENT
Thoracolumbar fascia; Ribs 6-12; Iliac crest

DISTAL ATTACHMENT
Linea alba; Pubic crest

ACTION
Bilateral: Compress abdominal contents (Corset; Girdle)
Bilateral: Stabilize lumbar spine & pelvis

INNERVATION
Ventral rami