Internal hernia as a rare cause of small bowel obstruction: An insight from 13 years of experience

Internal hernia (IH) is a rare culprit of small bowel obstruction (SBO) with an incidence of < 1%. It poses a considerable diagnostic challenge requiring a high index of suspicion to prevent misdiagnosis, improper treatment, and subsequent morbidity and mortality.

To determine the clinico-demographic profile, radiological and operative findings, and postoperative course of patients with IH and its association with SBO.

Medical records of 586 patients with features of SBO presenting at a tertiary care centre at Lucknow, India between September 2010 and August 2023 were reviewed.

Out of 586 patients, 7 (1.2%) were diagnosed with IH. Among these, 4 had congenital IH and 3 had acquired IH. The male-to-female ratio was 4:3. The median age at presentation was 32 years. Contrast-enhanced computed tomography (CECT) was the most reliable investigation for preoperative identification, demonstrating mesenteric whirling and clumped-up bowel loops. Left paraduodenal hernia and transmesenteric hernia occurred with an equal frequency (approximately 43% each). Intraoperatively, one patient was found to have bowel ischemia and one had associated malrotation of gut. During follow-up, no recurrences were reported.

IH, being a rare cause, must be considered as a differential diagnosis for SBO, especially in young patients in their 30s or with unexplained abdominal pain or discomfort post-surgery. A rapid imaging evaluation, preferably with CECT, is necessary to aid in an early diagnosis and prompt intervention, thereby reducing financial burden related to unnecessary investigations and preventing the morbidity and mortality associated with closed-loop obstruction and strangulation of the bowel.