Transversalis fascia is the lining fascia of the anterolateral abdominal wall which lies between the transversus abdominis muscle and peritoneum.
The transversalis fascia, inferior diaphragmatic fascia, pelvic fascia and iliacus fascia form a continuous lining of the abdominal and pelvic cavity:
- superiorly it is continuous with the inferior diaphragmatic fascia
- posteriorly it fuses with thoracolumbar fascia and is lost in the fat covering the posterior surface of the kidney
- inferiorly it is attached to the iliac crest and posterior margin of the inguinal ligament
- inferior to the inguinal ligament it is attached to the inguinal ligament by a fibrous tissue that forms the iliopubic tract
- medial to the femoral vessels it attaches to the pubis and pectineal line. It descends and forms the anterior part of the femoral sheath
The deep inguinal ring is an oval opening in the transveralis fascia located at the mid point of the inguinal ligament and is pierced by the spermatic cord in males and round ligament in females.
Below the umbilicus (at the arcuate line) the rectus sheath passes in front of the rectus abdominis muscle hence the muscle is only covered by transversalis fascia posteriorly at this level.