No 'safe zone' for low transverse incisions: ilioinguinal and iliohypogastric nerves.(Gynecology)

ANAHEIM, CALIF. -- There is no "safe zone" for placement of low transverse incisions that will reliably avoid the ilioinguinal and iliohypogastric nerves, although careful placement of lower abdominal laparoscopic trocars can minimize the chance of nerve injury, Dr. James Whiteside said.

Dr. Whiteside, a fellow in urogynecology at the Cleveland Clinic, said ilioinguinalal and iliohypogastric nerve injury is the second most common source of post-operative neuropathy following major pelvic surgery. The most common source of neuropathy is obturator injury (Obstet. Gynecol. 100[2]:240-44, 2002).

"Injury to these nerves is usually heralded by intense burning pain in the lower abdomen, upper medial thigh, and pelvic region, with altered skin sensations in these same areas. The pain typically intensifies with increased intra-abdominal pressure--coughing, sneezing, or Valsalva," he said at the annual meeting of the Society of Gynecologic Surgeons.

Neuropathic pain is poorly relieved by narcotics, although slight hip flexion may temporarily relieve pressure on the nerves, he noted.

To determine whether precise incision and trocar placement could avoid these nerves, Dr. Whiteside and associates dissected 11 fresh frozen cadavers placed in a dorsal supine position to expose the plane between the external and internal oblique muscles.

The investigators located the entrance and termination points of 13 iliohypogastric and 16 ilioinguinal nerves, ...