Malrotation

malrotation of gut

1. Malrotation Abhilash 11/09/2013

2. Introduction Malrotation – Group of congenital anomalies resulting from aberrant intestinal rotation and fixation. Takes place during the first three months of gestation. First reported by William Ladd in 1932.

3. Epidemiology Incidence : 1/6000 live births Most present < 1 month Incidence in general population – 0.2 to 0.5 % No sex/race predilection

4. Embryology 1. Herniation 2. Return to the abdomen. 3. Fixation. mutations in the forkhead box transcription factor FOX - familial malrotation

5. Key points in embryology Intestinal rotation starts at 5 th week. Midgut – SMA Rotation takes place around SMA axis 270 degree counterclock wise rotation of prearterial and post arterial limb. Ladds bands attach to the cecum irrespective of its postion at the end of rotation from right paracolic region.

6. Nonrotation Neither colon or duodenum undergo rotation Most common form of malrotation . M:F=2:1

7. Duodenum not posterior to SMA Ligament of Treitz fails to reach its normal position is right upper quadrant. Midgut mesentry is narrow and highly mobile. May cause Duodenal obstruction abnormal peritoneal bands. Acute midgut volvulus.

8. Incomplete rotation Counter clock wise rotation of only 180 degrees. Caecum in the epigastrium overlying 3 rd part of duodenum. Most common form of surgically treated malrolation .

9. REVERSE ROTATION Rotates clockwise. DJ loop anterior to SMA and transverse colon posterior to SMA. Causes Compression of colon by SMA -> obstruction. Ileocecal volvulus- due to inadequate fixation of right colon.

10. Stringers classification I – Non rotation of colon and duodenum IIA – Pure duodenal nonrotation IIB- Reversed rotation of duodenum and colon IIC – Reversed rotation of duodenum only IIIA – Nonrotation of colon IIIB- Incomplete fixation of hepatic flexure IIIC- Incomplete attachment of cecum and mesocecum

11. Associated anomalies(seen in 30%-60%) Duodenal atresia / stenosis / web Congenital diaphragmatic hernia Gastroschisis Omphalocele Choanal atresia Polysplenia / asplenia Congenital megacolon

12. How does it present. Asymptomatic Midgut volvulus Mesocolic hernias. Duodenal and jejunal obstruction. Colonic obstruction.

13. Clinical features in adults Intermittent cramping or persistent aching pain. Severe abdominal cramping followed by diarrhea - chronic volvulus . Vomiting - bilious /non bilious , variable in duration and frequency. Malabsorption - diarrhea, nutritional deficiencies Rare - obstructive jaundice, chylous ascites and superior mesenteric vein thrombosis

14. Plain radiograph No pathognomonic signs. Right-sided jejunal markings Absence colonic shadow in RIF Features of complications - Dilated bowel loops - Air fluids levels - Pneumoperitoneum

15. Ultrasound Reversal of the normal anatomic relationship between the SMA and “ whirlpool sign” - midgut volvulus. “bird beak” appearance – duodenal obstruction. false-positive rates of up to 21%

16. Upper GI contrast study >incomplete duodenal obstruction, usually in the third portion; >ligament of Treitz not to the left of the midline or at the level of the gastric antrum ; >abnormal position of the proximal jejunal loops to the right of the midline; and >deformity of the duodenum with a bird's beak , corkscrew, or coiled configuration

17. CT Abdomen Anatomic location of small bowel on right and colon on left Relationship of the superior mesenteric vessels – “vertically placed or inverted sides” Aplasia of the uncinate process Features of volvulus / obstruction / gangrene Other associated anomalies

18. Reversal of SMA and SMV Whirlpool sign

19. Management Supportive management. Surgical management – Ladds procedure.

20. Ladd's procedure

21. Post operative care nasogastric decompression total parenteral nutrition until return of bowel function.

22. Mortality from midgut volvulus with severe bowel compromise may exceed 30 %. Long-term complications adhesive small bowel obstruction (10%), r ecurrent volvulus, short gut syndrome.

23. References Ladd WE. Congenital obstruction of the duodenum in children. N Engl J Med. 1932;206:277–83 . Principles and Practice of Pediatric Surgery, 4th Edition. Keith T Oldam . Shackelford’s Surgery of the Alimentary tract 7 th edition. Stringer Pediatric Gastrointestinal Imaging and Intervention, 2 nd edition