[The ilioinguinal and iliohypogastric nerves. The anatomic bases in preventing postoperative neuropathies after...

To identify danger areas in surgical incisions (appendectomy, inguinal and Pfannenstiel incisions) by mapping the course of ilioinguinal and iliohypogastric nerves.

The courses of the ilioinguinal and iliohypogastric nerves from 37 unembalmed adult cadavers were mapped from their lateral emergence on the internal obliquus nerve to their midline termination in reference to anatomic landmarks (anterior superior iliac spine, midline, upper border of the pubic symphysis). With use of a mapping technique, the standard courses of both nerves were compared with sites of standard abdominal surgical incisions.

Sixty seven ilioinguinal and sixty four iliohypogastric nerves were identified and mapped. On average the ilioinguinal nerve perforated the internal obliquus muscles 3.30 cm medial and 3.27 inferior to the anterior superior iliac spine, and terminated its course 2.50 cm lateral to the midline and 1.92 cm superior to the upper border of the pubic symphysis. On average the iliohypogastric nerve perforated the internal obliquus muscles 2.30 cm medial and 1.20 cm inferior to the anterior superior iliac spine, and terminated its course 3.10 cm lateral to the midline and 4,80 cm superior to the upper border of the pubic symphysis.

Surgical incisions performed below the level of the anterior superior iliac spine carry the risk of injury to the ilioinguinal and iliohypogastric nerves.