Muscle
Transversus abdominis
Deepest flat abdominal muscle
High-yield
Transverse fibres act as a "corset"; core-stability muscle. Contributes to the conjoint tendon.
Overview
The deepest flat abdominal muscle with transverse fibres that compress and support the abdominal viscera like a corset.
Reference facts
- Origin
Thoracolumbar fascia, iliac crest, lateral inguinal ligament, and costal cartilages 7–12
- Insertion
Linea alba, pubic crest, and pectineal line (conjoint tendon)
- Action
Compresses and supports the abdominal viscera; increases intra-abdominal pressure
- Innervation
Thoracoabdominal nerves (T7–T12), subcostal, and L1
- Blood supply
Lower posterior intercostal / deep circumflex iliac arteries