Internal Herniation of Small Bowel Underneath Iliac Vascular Axis After Pelvic Surgery: A Systematic Review

Internal abdominal hernias are rare entities that most commonly present with acute small bowel obstruction. These hernias can be congenital or acquired. While congenital hernias are considered the most common type, acquired hernias are becoming more common. Recently, a rare type of internal herniation has been reported underneath iliac vasculature in patients who have undergone pelvic lymph node dissection in the past. This study was carried out to assess the prevalence of this rare type of internal hernia. Two reviewers searched the literature in three online databases using the Cochrane methodology for systematic reviews. The search of databases yielded 70 articles. The studies which reported internal herniation underneath iliac vasculature were included. Studies that reported herniation underneath other pelvic organs or vasculature were excluded. After screening, 17 articles were deemed suitable and selected. All 17 cases reviewed underwent pelvic lymph node dissection in the past. The median latency period between index surgery and clinical presentation with the incarcerated hernia was 20 months. All 17 cases were managed surgically with small bowel resection carried out in 13 cases. Eleven authors reported closing the hernia defect with various techniques, while five decided not the close it. All 17 cases were alive at the time of discharge from the hospital, with a mean hospital stay of 12.7 days. Given our findings, there should be a high index of suspicion of internal hernia in patients presenting with small bowel obstruction with a history of pelvic lymph node dissection. In our review, internal herniation was always preceded by pelvic lymph node dissection, so the closure of the peritoneum should be considered while pelvic lymph node dissection is carried out.