To explore the anatomical relationship between the membranes of preperitoneal space in totally extraperitoneal (TEP) and identify the operative level through posterior approach repair.

A total of one hundred and twenty patients undergoing TEP from July 2016 to May 2019 in Chashan Hospital of Guangdong Medical University were retrospectively studied. The intraoperative observation, complication analysis and postoperative follow-up were recorded.

The traditional arcuate line (4-5 cm) was in 36 cases (30.0%), while the low arcuate line (6-12 cm) was in 84 cases (70.0%). The sharp well-defined arcuate line accounted for 31.7% in 38 cases, while the ill-defined flimsy one for 68.3% in 82 cases. The Retzius space was located between the transversalis fascia and the superficial layer of the preperitoneal fascia, while the Bogros space separated outward between the peritoneum and the deeper layer of the preperitoneal fascia. The discontinuity of two layers was connected by resecting the interfaveolar ligament, creating a preperitoneal space big enough to accommodate the patch. The incidence of peritoneum injury was 5.0% (6/120), no epigastric vessels were injured. No recurrence was found after an median follow-up of 22 months.

The knowledge of the anatomy of membranes of preperitoneal space is helpful to improve the safety and efficacy of the procedure, and reduce the complications and recurrence.