The suspensory muscle of the duodenum and its nerve supply.

The gross anatomy, microscopic structure and nerve supply of the suspensory muscle of the duodenum and Hilfsmuskel have been studied in cadavers of 88 adults, 5 children, 1 infant and 6 neonates. The suspensory muscle of the duodenum, consisting of plain muscle fibres, arose from the connective tissue around the stems of the coeliac and superior mementeric arteries. It was inserted into the third and fourth parts of the duodenum in 53%, and into the duodeno-jejunal flexure in addition in 40%. It was innervated by non-myelinated fibres arising from the coeliac and superior mesenteric plexuses. Although both the longitudinal and circular muscle coats of the duodenum extended into the suspensory muscle, it was not supplied by Auerbach's plexus. The Halfsmuskel, which is a slip of the diaphragm is attached above to the margin of the oesophageal hiatus and below to the connective tissue in the region of the stem of the coeliac artery, sometimes extending to the stem of the superior mesenteric artery. The Hilfmuskel and the suspensory muscle of the duodenum are separate entities.