Internal hernia beneath the obturator nerve after robot-assisted lateral lymph node dissection for rectal cancer: A case report and literature review.

A 63-year-old man who underwent robot-assisted laparoscopic low anterior resection and right lateral lymph node dissection (LLND) for rectal cancer presented with right thigh pain, nausea, vomiting, and abdominal pain on postoperative day 17. CT revealed dilated small bowel in the pelvis, and a small bowel loop was detected outside the internal iliac artery branch. Emergent laparoscopic surgery revealed the migration of the small bowel into the space beneath the right obturator nerve. The herniated bowel was reduced, and the obturator nerve was sharply dissected from the herniated bowel and preserved. The hernial orifice was left unrepaired. Postoperative recovery was uneventful, and the right thigh pain disappeared. It is important to consider the possibility of internal herniation beneath the obturator nerve after minimally invasive lateral lymph node dissection for rectal cancer.