Structures traveling between the thorax and abdomen pass through the diaphragm or between the diaphragm and its peripheral attachments:
The inferior vena cava passes through the central tendon at approximately vertebral level TVIII.
The esophagus passes through the muscular part of the diaphragm, just to the left of midline, approximately at vertebral level TX.
The vagus nerves pass through the diaphragm with the esophagus.