Structures

  • Rectus abdominis
  • External oblique
  • Internal oblique
  • Psoas minor
MuscleActionOriginInsertionInnervationBlood supply
Rectus abdominis- Compress abdominal cavity
- Flex lumbar spine
- Pubic crest- Costal cartilages of ribs 5-7;
- Anterior rami of T7-T12- Superior epigastric artery
- Inferior epigastric artery
- Superficial epigastric artery
External oblique- Compress abdominal cavity
- Rotate trunk to opposite side
- Weak flexion of lumbar spine
- Aid expiration by compressing lower thoracic cage
- Lateral surfaces of the lower eight ribs (ribs 5 to 12)- Lateral iliac crest
- Aponeurosis to end at linea alba (midline raphe)
- Anterior rami of T7-12 thoracic spinal nerves - Lower posterior intercostal and subcostal arteries
- Superior and Inferior epigastric arteries
- Superficial and deep circumflex iliac arteries
- Posterior lumbar arteries
Internal oblique- Compress abdominal cavity
- Rotates trunk to same side
- Weak flexion of lumbar spine
- Thoracolumbar fascia
- Iliac crest
- Lateral 2/3 of inguinal ligament
- Inferior border of the lower 3-4 ribs
- Aponeurosis which ends in linea alba;
- Pubic crest
- Anterior rami of T7-T12 thoracic spinal nerves and L1- Lower posterior intercostal and subcostal arteries
- Superior and Inferior epigastric arteries
- Superficial and deep circumflex iliac arteries
- Posterior lumbar arteries
Psoas minor- Weak flexion of lumbar vertebral column- Bodies of T12-L5 vertebrae
- Intervertebral discs between T12-L5
- Pectineal line of the pelvic brim - Anterior rami of L1- Lumbar branch of iliolumbar artery