FIGURE 116.10 A: Malrotation of the bowel Supine plain roentgenogram of the abdomen shows distended stomach and proximal duodenal loop B: Same patient as in (A ) Upper gastrointestinal series shows dilated proximal duodenum with abrupt transition to normal caliber of small bowel Abnormally placed ligament of Treitz Proximal jejunum in the right abdomen On physical examination, there may be only mild distension of the abdomen because the obstruction usually occurs high in the GI tract On palpation, the physician may discern one or two prominently dilated loops of bowel The abdomen may be diffusely tender and yet not have signs of peritonitis early in the course On rectal examination, the presence of blood on the examining finger is an alarming sign of impending ischemia and gangrene of the bowel Management The key to management is to be suspicious of malrotation and to obtain supine and upright radiographs of the abdomen immediately The presence of loops of small bowel overriding the liver shadow is suggestive of an underlying malrotation When complete volvulus has occurred, there may be only a few dilated loops of bowel with air–fluid levels Distal to the volvulus, there may be little or no gas in the GI tract A “double-bubble sign” is often present on an upright film because of partial obstruction of the duodenum causing distension of the stomach and first part of the duodenum ( Fig 116.10A ) When a child is being assessed for possible malrotation (with or without volvulus), an upper GI series is the study of choice The ligament of Treitz is absent in the malrotation anomaly; therefore, the C-loop of the duodenum is not present, the duodenum lies to the right of the spine, and the jejunum presents a coiled spring appearance in the right upper quadrant ( Figs 116.10B and 116.11 ) The cecum is not fixed and usually assumes a position in the right upper quadrant However, because of its mobility, the cecum on barium enema may be seen in its normal position in the right lower quadrant Therefore, a barium enema is not the most reliable study to rule out malrotation In the neonate, the cecum