Thoracic Diaphragm

Figure 1:Thoracic Diaphragm shape and position

• Thoracic Diaphragm is a striated muscle that separates the Thoracic cavity from the abdomen cavity. It is like an open umbrella which divided into 2 parts and connected in the center with convexity towards the thorax. It contracts continually as you breathe in and out.
• The muscle fibers of diaphragm emerge from many surrounding structures. At the front, it attaches to the xiphoid process of the sternum from its backside and the costal cartilage of Rib 7-to Rib 10. Laterally it s connected the rib 7-12 and at the backside, it is connected to the Lumber vertebrae-L1-L2. 
• It very near to Heart, Lungs in thorax and Liver, stomach, and spleen in the abdomen.
• Diaphragm contracts and flattens when we inhale and this enlarges the thoracic cavity so the pressure within the thoracic cavity gets decreased. And air flows from high pressure to low pressure so air goes into our lungs. When we exhale, the diaphragm relaxes and the air is pushed out of lungs.
• It also has some nonrespiratory functions as well. The diaphragm increases abdominal pressure to help the body get rid of vomit, urine, and feces. It also places pressure on the esophagus to prevent acid reflux.
• The phrenic nerve, which runs from the neck to the diaphragm, controls the movement of the diaphragm.
• There are three large openings in the diaphragm that allow certain structures to pass between the chest and the abdomen. These openings include the:
• Esophageal opening-The esophagus and vagus nerve, which controls much of the digestive system, pass through this opening.
• Aortic opening- The aorta, the body’s main artery that transports blood from the heart, passes through the aortic opening. The thoracic duct, a main vessel of the lymphatic system, also passes through this opening.
• Caval opening- The inferior vena cava, a large vein that transports blood to the heart, passes through this opening.

Figure 2: Thoracic Diaphragm Structure

References:

• Gnosis Medical Yoga Teacher textbook
• https://yogamedicine.com/power-diaphragm-part/