Expansion
A continuous fascial sheet whose defect forms the deep inguinal ring
Expansion
Transversalis fascia is the continuous layer of fascia lining the entire abdominal wall, deep to transversus abdominis and superficial to the extraperitoneal fat.
In the groin it does two things:
- It is evaginated at the deep inguinal ring to form a tubular prolongation around the cord, the internal spermatic fascia. The ring is therefore a defect in fascia, not in muscle, and lies at the mid-point of the inguinal ligament, just lateral to the inferior epigastric vessels
- It forms the posterior wall of the inguinal canal, and is the only barrier across Hesselbach’s triangle
A direct hernia is therefore a failure of transversalis fascia, while an indirect hernia follows a pre-existing fascial tube.
Modern tension-free repairs reinforce this fascia with mesh rather than trying to restore it by suturing, which is why recurrence rates fell so dramatically after their introduction.