Narrow intercostal space

Twelve pairs of ribs participate in the rib cage, and the space between the ribs is the intercostal space. There are intercostal muscles, blood vessels, nerves and connective tissue membranes. The width of the intercostal space varies, the upper intercostal space is wider and the lower one is narrower; the intercostal space is wider at the front and narrower at the rear, but can vary with body position.