The musculophrenic artery is a branch of the internal thoracic artery. It runs parallel to the lower border of the pectoralis major muscle and supplies blood to the diaphragm and intercostal muscles. Other terms that can be used interchangeably with musculophrenic artery include intercostal artery and internal mammary artery. Intercostal arteries are blood vessels that run between the ribs, providing oxygenated blood to the chest wall. On the other hand, internal mammary arteries supply blood to the chest and are used in coronary artery bypass surgery. Although these terms are slightly different, they are used in a related context and are considered synonymous.