Laparoscopic inguinal anatomy

Summary

Irrespective of the merits of laparoscopic herniorrhaphy, the anatomy of this surgical approach is poorly understood by most surgeons. To describe and document the normal analtomy and its variations, the inguinal region was dissected from peritoneum outward by the open method in 70 cadaveric sides and by the closed laparoscopic method in 28 cadaveric sides. In our results we describe the various layers, fossae, spaces and their contents. The data presented include variations of nerves in the inguinal area and measurements of bony landmarks from important neurovascular elements. In 74%, the distance from anterior superior iliac spine (ASIS) to pubic tubercle (PT) was 11 cm (10.0–14.0); in 56% ASIS to external iliac vessels was 6 cm (4.5–7.5 cm); ASIS to femoral nerve in 64% was 5 cm (3.0–7.5). The lateral femoral cutaneous nerve was found 1–4.5 cm medial to ASIS in 15%, increasing the possibility of nerve injury. In 25.5% the ilioinguinal nerve ran through the iliac fossa, in some cases passing through the iliopubic tract. In 18% the lateral femoral cutaneous and ilioinguinal nerves were combined, and in 7.7% the ilioinguinal and genitofemoral nerves were combined. It is critical for laparoscopic surgeons to be aware of the normal inguinal anatomy and its variants to avoid unnecessary injury and pain. It is important to remember that in approximately 30% of cases, the laparoscopic anatomy of one side will not be a mirror image of the other side.