The lower opening of the thorax is formed by the twelfth thoracic vertebra behind, by the eleventh and twelfth ribs at the sides, and in front by the cartilages of the tenth, ninth, eighth, and seventh ribs, which ascend on either side and form an angle, the infrasternal angle or subcostal angle, into the apex of which the xiphoid process projects.

The "subcostal angle" is the angle between the xiphoid process and the right or let costal margin. Normally, during inhalation the chest expands laterally, increasing this angle. When the diaphragms are flattened (as in COPD), inhalation paradoxically causes the angle to decrease.

The infrasternal angle (subcostal angle) is formed in front of thoracic cage by the cartilages of the tenth, ninth, eighth, and seventh ribs, which ascend on either side, where the apex of which the xiphoid process projects.

2022年12月22日 · At this point of attachment the subcostal angle is formed. The costal margin forms the lower margin of the thoracic wall. It functions to protect higher abdominal organs such as the liver as the greater part of the liver lies just below the right costal margin.

2023年6月6日 · The xiphoid process is part of the inferior margin of the thoracic cavity and marks the infrasternal angle (subcostal angle) of the inferior thoracic aperture. Test your knowledge on the sternum with the following quiz!

2023年11月3日 · Subcostal muscles originate from the inner surface of one rib near its posterior angle. Their fibers descend inferomedially in the same fashion as those of the innermost and internal intercostals. Each subcostal muscle inserts to the inner surface of the second or third rib below its origin.

The normal subcostal angle is 90°. It is more acute in males than in females. Empyema necessitans in which there is an intercostal swelling close to the sternum. Swelling due to empyema necessitans. Kyphosis (forward bending of …