Initially, the dorsal mesentery of esophagus (meso-esophagus) forms median portion of the diaphragm. Finally, the mesenchyme of the meso-esophagus condenses at the level of L1 to L3 vertebrae to form two muscular bands, called right and left crura of the diaphragm. Each crus originates
on the vertebral column and inserts into the dorsomedial part of the diaphragm.