TRANSVERSUS ABDOMINIS
| ORIGIN Costal margin, lumbar fascia, anterior two thirds of iliac crest and lateral half of inguinal ligament |
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| INSERTION Aponeurosis of posterior and anterior rectus sheath and conjoint tendon to pubic crest and pectineal line |
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| ACTION Supports abdominal wall, aids forced expiration and raising intra-abdominal pressure. Conjoint tendon supports posterior wall of inguinal canal |
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| NERVE Anterior primary rami (T7-12). Conjoint tendon ilioinguinal nerve (L1) |