|Origin||Costal cartilages of the seventh to twelfth ribs
Pubic crest via conjoint tendon
Pectineal line via conjoint tendon
|Action||Provides structural support to adjacent abdominal structures
Compresses abdomen and increases intrabdominal pressure
|Nerve||Intercostal nerves (T7-T11)
Subcostal nerve (T12)
Iliohypogastric nerve (L1)
Ilioinguinal nerve (L1)
|Artery||Lower posterior intercostal artery
Superficial and deep circumflex iliac arteries
Inferior and superior epigastric arteries
Location & Overview
The transversus abdominis (sometimes abbreviated to ‘TVA’) is one if the five abdominal muscles. The other four are: the external oblique, internal oblique, rectus abdominis and the pyramidalis. The transversus abdominis muscle is the deepest of the anterolateral abdominal muscles. Its fibres run transversely and continue to the linea alba at the midline of the abdomen. The transversus abdominus is also one of the three muscles which form the rectus sheath. The rectus sheath is comprised of the internal oblique and external oblique muscles in addition to the transversus abdominis. The rectus sheath surrounds the rectus abdominis muscle and the pyramidalis muscle. They both sit within the rectus sheath like how a sword would be kept in a sheath (which is the reason for its name)   .
Origin & Insertion
The transversus abdominis muscle originates from the costal cartilages of seventh to twelfth ribs, thoracolumbar fascia, iliac crest, and inguinal ligament. It then inserts into the linea alba. It also inserts onto the pubic crest and pectineal line via the conjoint tendon. The pectineal line is also known as the pecten pubis. The conjoint tendon is formed by the lower sections of the aponeurosis of the transversus abdominis and the internal oblique.  .
The role of the transversus abdominis muscle is to compress and provides structural support to adjacent abdominal structures. This compression of the abdominal area can increase intrabdominal pressure. Furthermore, this compression can draw the belly button inwards and is involved in the ‘vacuum exercise’. The compression of the abdomen can also assist in forced expiration  .
The transversus abdominis muscle gets its blood supply from the lower posterior intercostal artery, subcostal artery, superficial and deep circumflex iliac arteries, and inferior and superior epigastric arteries  .
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Transversus Abdominis Flashcards
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|↑2, ↑4||Flynn W, Vickerton P. Anatomy, Abdomen and Pelvis, Abdominal Wall. [Updated 2021 Jul 31]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK551649/|
|↑3, ↑5, ↑6, ↑8, ↑10||Moore KL, Agur AMR, Dalley AF. Clinically Oriented Anatomy. 8th ed. Philadelphia: Lippincot Williams & Wilkins; 2017.|
|↑7||Hides J, Wilson S, Stanton W, McMahon S, Keto H, McMahon K, Bryant M, Richardson C. An MRI investigation into the function of the transversus abdominis muscle during “drawing-in” of the abdominal wall. Spine (Phila Pa 1976). 2006 Mar 15;31(6):E175-8. doi: 10.1097/01.brs.0000202740.86338.df. PMID: 16540858.|
|↑9, ↑11||Seeras K, Qasawa RN, Ju R, et al. Anatomy, Abdomen and Pelvis, Anterolateral Abdominal Wall. [Updated 2021 Jul 26]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK525975/|