Right-side fixation of the sigmoid colon causing internal herniation with closed-loop obstruction of both small and large bowel: a case report and review of the literature

A 65-year-old Caucasian man was admitted to our hospital with a 12-hour history of diffuse colicky abdominal pain, nausea, and vomiting. The pain had arisen suddenly and presented a gross localization to the upper quadrants. He had failed to pass feces and gas for the last 2 days and reported no significant abdominal symptoms before the event except for mild stypsis. His past medical history included a previous thoracoscopic mitral valve repair and mild renal insufficiency secondary to ectopic hypoplastic left kidney located in the pelvis. He had no history of previous abdominal surgery. Upon physical examination, we found significant abdominal distension, severe spontaneous pain in the upper abdomen without guarding or positive Blumberg sign, and tympany on percussion. The body temperature was 37 °C, and all vital parameters were normal. Digital rectal examination revealed empty ampulla with normal fecal residues. A nasogastric tube was positioned, and about 400 ml of biliary effluent was drained.

Blood tests revealed neutrophilia (leukocytes 9.98 × 103/μl; neutrophils 9.08 × 103/μl) and elevated C-reactive protein (CRP; 65 mg/L). Abdominal X-ray, in turn, showed diffuse abdominal distension of both small and large bowel with multiple air–fluid levels. The small bowel presented valvulae conniventes without mucosal thickening, while the large bowel showed coprostasis and regular haustration. Cecum diameter measured about 6 cm (Fig. 1).

Abdominal contrast-enhanced computed tomography (CT) scan was thus performed showing an anatomical abnormality of the colon and diffuse dilation of both the small bowel and colon. The sigmoid colon was elongated and formed a distended loop in the subhepatic recess above the right flexure. Cecum and ascending colon were in their normal position, while the left ectopic kidney was found on the left side of the pelvis. Pancreas, duodenum, right kidney, celiac trunk, and superior mesenteric artery had no significant abnormalities (Fig. 2).

Importantly, the lack of left kidney bulk in the left flank altered the course of the colonic portions corresponding to the splenic flexure and descending segment. The splenic flexure was twisted counterclockwise on the frontal plane, causing the descending colon to be more medial and posterior. The latter therefore crossed posteriorly to the body of pancreas near the L2 vertebral body and descended anteriorly to the psoas muscle. From there onward, the course of the sigmoid colon could be divided into four segments. The first segment began in the left iliac fossa, turning right and crossing the midline at the level of the L5–S1 intervertebral disc near the upper pole of the left ectopic kidney. The second segment turned sharply upward directed to the subhepatic recess running anterior to the inferior vena cava and crossing the right common iliac artery anteriorly and the ileocolic vessels and proximal transverse colon posteriorly. The third segment formed a dilated loop in contact with the gallbladder and the lower aspect of the right hepatic lobe. The fourth segment continued in an inferior direction running along the right side of the inferior vena cava, crossing the right side of the promontory, and terminating in the rectum. Since the third part was dilated to 5 cm in diameter and the second and fourth parts were compressed, the sigmoid colon appeared to be involved in a closed-loop occlusion. A C-shaped fluid-filled loop of ileum with beak-like proximal and distal narrowing was found near the fourth part of sigmoid colon, resembling a closed-loop small bowel obstruction. Both the ileal loop and the sigmoid colon appeared to be incarcerated in a narrow space behind the ileocolic vessels.

The inferior mesenteric artery (IMA) was also characterized by an abnormal course. This originated from the aorta 2.5 cm above the aortic bifurcation and ran rightward, giving rise to a long recurrent left colic artery and some directed upward sigmoid branches. It then turned downward into the pelvis as the superior hemorrhoidal artery. The left colic artery had an extremely long course: it originated from the IMA via a common trunk with the first sigmoid artery to the right side of the aorta and crossed it running left and upward. The left renal artery originated on the anterior face of the aortic bifurcation and flowed downward to the ectopic kidney located on the left in the small pelvis (Fig. 3).

Given the complex anatomy, we opted for exploratory laparoscopy, which revealed a recess on the right posterior peritoneum traversed by the sigmoid colon. An ileal loop was trapped within this space, resulting in an internal hernia with upstream bowel dilation. This recess was limited anteriorly by Toldt’s fascia, the ascending colon and adhesions spanning between the ascending colon and the abdominal wall. These adhesions were similar to the Ladd’s bands described in malrotations. The ileal loop was extracted from the recess and did not appear ischemic, with deflation ensuing shortly after this procedure. The sigmoid colon was then extracted, revealing thick adhesions between the sigmoid colon and the posterior abdominal wall forcing the sigmoid colon to recoil inside the recess once traction from laparoscopic clamp was eased. Given the inability to safely lyse these adhesions, we decided to convert to open surgery. The adhesions of the sigmoid colon and its mesosigmoid with the retroperitoneum were partially lysed, allowing the sigmoid colon to remain in natural position without tension. Thereafter, a suture of the hernial breach was performed between the lower edge of Toldt’s fascia and the retroperitoneum. We did not perform complete lysis of sigmoid colon adhesions as this would have led to the complete mobilization of a dolichosigma with significant risk of volvulus. The procedure was completed with appendicectomy and positioning of abdominal drainage in the pelvis (Fig. 4).

The postoperative course was free of complications. Resumption of peristalsis was on the fifth postoperative day with re-alimentation beginning on the third postoperative day. The drainage was removed on the fifth postoperative day, and the entire hospital stay lasted 7 days. The patient did not report further symptoms except for the persistence of mild stypsis neither at postoperative day 12 nor at 6-month follow-up.