Expansion
A fibromuscular band suspending the duodenojejunal flexure from the right crus of the diaphragm
Expansion
The suspensory muscle of the duodenum runs from the right crus of the diaphragm and the connective tissue around the coeliac trunk down to the duodenojejunal flexure. It contains both skeletal and smooth muscle and helps widen the angle of the flexure to aid the passage of contents.
It has three clinical uses:
- Dividing line for gastrointestinal bleeding - proximal is “upper”, distal is “lower”
- Landmark for the start of the jejunum, and for identifying the proximal small bowel at laparotomy
- Marker of malrotation - in normal anatomy the flexure lies to the left of the midline at the level of L2; a flexure lying low or to the right indicates malrotation
Its position at the transpyloric plane also makes it a fixed reference point on cross-sectional imaging.