[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Anatomy](https://durgical.com/en/anatomy/) › [Abdomen](https://durgical.com/en/anatomy/region/abdomen/) › Transversalis fascia [Muscular system](https://durgical.com/en/anatomy/system/muscular-system/) · [Abdomen](https://durgical.com/en/anatomy/region/abdomen/) # Transversalis fascia The transversalis fascia is a thin layer lining the inside of the abdominal wall; weak spots in it in the groin are where inguinal hernias form. [See in 3D →](https://durgical.app/?from=durgipedia&lang=en#region=abdomen&select=transversalis_fascia&side=r) Opens in the Durgical app, no sign-up needed. ## What it is A thin sheet lining the inside of the abdominal muscles, just outside the peritoneum. ## What it does The layer that a hernia pushes through; in laparoscopic hernia repair the mesh is laid against it. ## Key points - Its weakness in Hesselbach triangle allows the direct inguinal hernia; the deep inguinal ring is a hole in it - Below the arcuate line it is the only layer (with the peritoneum) behind the rectus abdominis - Continues into the thigh as the front wall of the femoral sheath, with the iliac fascia forming the back wall - Laparoscopic hernia repair places mesh in the preperitoneal space just deep to it, covering the direct, indirect and femoral openings at once ## Key facts **Where** Deep to transversus abdominis, between it and extraperitoneal fat; part of the endoabdominal fascia **Attaches** Iliac crest and inguinal ligament; continuous with iliac and psoas fascia; evaginates at deep inguinal ring as internal spermatic fascia **Function** Forms posterior wall of [inguinal canal](https://durgical.com/en/anatomy/inguinal-canal/); weak area in Hesselbach's triangle is where direct inguinal hernias push through ## Relations **Superficial** [Transversus abdominis](https://durgical.com/en/anatomy/transversus-abdominis-muscle/) and its aponeurosis; below the arcuate line, the [rectus abdominis](https://durgical.com/en/anatomy/rectus-abdominis-muscle/) **Deep** Extraperitoneal (preperitoneal) fat and parietal [peritoneum](https://durgical.com/en/anatomy/peritoneum/); the inferior [epigastric vessels](https://durgical.com/en/anatomy/inferior-epigastric-artery/) run in this fat before entering the [rectus sheath](https://durgical.com/en/anatomy/rectus-sheath/) **Above** Continuous with the fascia on the undersurface of the [diaphragm](https://durgical.com/en/anatomy/diaphragm/) **Below** Attaches to the iliac crest and the inner edge of the [inguinal ligament](https://durgical.com/en/anatomy/inguinal-ligament/); thickened as the iliopubic tract and carried into the thigh as the femoral sheath **Behind** Continuous with the fascia over [quadratus lumborum](https://durgical.com/en/anatomy/quadratus-lumborum-muscle/) and [psoas major](https://durgical.com/en/anatomy/psoas-major/) (the endoabdominal fascia) ## How to find it In open groin repair it is the thin posterior wall of the inguinal canal seen once the [spermatic cord](https://durgical.com/en/anatomy/spermatic-cord/) is lifted. At laparoscopy it is reached by lifting the peritoneum and extraperitoneal fat off the inside of the wall. ## On imaging Not seen as a separate layer on radiographs. On CT and ultrasound it is a thin line deep to transversus abdominis, hard to separate from the muscle, with extraperitoneal fat behind it. In the groin it is a key landmark: a direct inguinal hernia pushes through its weak area medial to the inferior epigastric vessels, which ultrasound and CT use to tell direct from indirect hernias. ## Common problems - Hernias: a weak spot lets fat or bowel bulge through (groin, belly button, old incisions). - Muscle strains. ## How it is diagnosed Examination, often while coughing or standing; ultrasound or CT if unclear. ## Treatment - Hernias that cause symptoms are repaired, usually with a mesh. ## Clinical notes - Direct hernias bulge through a thinned transversalis fascia; tissue repairs (such as the Shouldice technique) rebuild it in layers - Laparoscopic repair landmarks: the triangle of doom (between [ductus deferens](https://durgical.com/en/anatomy/ductus-deferens/) and [testicular vessels](https://durgical.com/en/anatomy/testicular-artery/), over the external iliac vessels) and the triangle of pain (lateral, below the iliopubic tract, with the [lateral femoral cutaneous nerve](https://durgical.com/en/anatomy/lateral-femoral-cutaneous-nerve/) and femoral branch of the [genitofemoral nerve](https://durgical.com/en/anatomy/genitofemoral-nerve/)) are kept free of tacks - The femoral canal, the medial compartment of the femoral sheath, is the path of the femoral hernia - At the deep ring it forms the internal spermatic fascia, the innermost covering of the spermatic cord ## Related conditions - [Inguinal hernia](https://durgical.com/en/conditions/inguinal-hernia/) - [Incisional (ventral) hernia](https://durgical.com/en/conditions/incisional-hernia/) - [Femoral hernia](https://durgical.com/en/conditions/femoral-hernia/) ## Test yourself Think of the answer, then tap the question to see it. ## Which inguinal hernia pushes through the transversalis fascia in Hesselbach triangle? The direct inguinal hernia, through a thinned transversalis fascia; the deep inguinal ring, entry of the indirect hernia, is itself a hole in this fascia. ## What does the transversalis fascia form at the deep inguinal ring? The internal spermatic fascia, the innermost covering of the spermatic cord. ## What does the transversalis fascia become in the thigh? The front wall of the femoral sheath (iliac fascia forms the back); its medial compartment, the femoral canal, is the path of a femoral hernia. ## Where is the mesh placed in laparoscopic groin hernia repair? In the preperitoneal space just deep to the transversalis fascia, covering the direct, indirect and femoral openings at once. [Add to my cards (4)](https://durgical.app/estudiar/?add=/en/anatomy/transversalis-fascia/) Educational information, not medical advice. For any symptom, see a health professional. ## Its names **Official Latin (TA2)** fascia transversalis TA2 2389 **Official Spanish (DeCS)** Fascia transversal **English (TA2)** Transversalis fascia ## Related - [Transversus abdominis](https://durgical.com/en/anatomy/transversus-abdominis-muscle/) - [Peritoneum](https://durgical.com/en/anatomy/peritoneum/) Sources: Terminologia Anatomica (TA2); [Anatomy, Abdomen and Pelvis: Anterolateral Abdominal Wall Fascia](https://www.ncbi.nlm.nih.gov/books/NBK459392/). ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/anatomy/transversalis-fascia/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/anatomy/transversalis-fascia/