Yogabody: Anatomy, Kinesiology, and Asana

The phrenic nerve arises from fibers of the third, fourth, and fifth cervical nerves on both sides of the neck. Therefore there are two phrenic nerves, the right and the left. The left phrenic nerve is actually longer, in part due to the placement of the heart.

The major motor nerve to the diaphragm is the phrenic nerve (Figure 12.3). Phrenic is related to the word frantic. In Greek, phren has as its secondary meaning “the mind, as the seat of the intellect or the heart as the seat of the passions.”

splits into other structures; the opening for the esophagus; and the opening for the vena cava, which is the vein bringing blood from the lower body to the heart. There are also openings for the passage of nerves and smaller veins.

The biggest three are the opening for the aorta, as it descends from the heart through the thorax to abdomen, where it

The fascia of the abdomen also connects the vertebrae, the psoas muscles, and the kidneys to the diaphragm at the muscular insertions. In fact, basically all organs both above and below the diaphragm area are connected to the diaphragm in some way, and thus the act of respiration moves them all.

The central tendon is an aponeurosis that is located just distal to the pericardium, the covering of the heart; the fascial tissue of the thorax connects the diaphragm to the pericardium.

At the posterior diaphragm are two tendinous structures called crura. The right crus arises from the intervertebral discs and vertebral bodies of the first three lumbar vertebrae. The left crus arises from the intervertebral discs and vertebral bodies of only the first two lumbar vertebrae. Both insert into the clover-shaped central tendon of the d

The diaphragm is attached to the xiphoid process of the sternum and the inner surfaces of the costal cartilages of the lower six ribs (Figure 12.1). The bodies of the first three lumbar vertebrae are also attached to the diaphragm.

menisci.