Musculophrenic Artery

arteria musculophrenica

The musculophrenic artery is one of the two terminal branches of the internal thoracic artery (the other being the superior epigastric artery), arising at the level of the sixth costal cartilage. It runs laterally and inferiorly along the costal margin, perforating the diaphragm to supply the diaphragm and the lower intercostal spaces. It also gives anterior intercostal branches to the 7th, 8th, and 9th intercostal spaces.

Region: Chest

Clinical Relevance

Clinical Notes

The musculophrenic artery is an important collateral pathway between the internal thoracic and the phrenic circulation. It is encountered during subcostal port insertion for laparoscopy and during thoracoabdominal approaches that traverse the costal margin. The musculophrenic artery is sacrificed when harvesting the lower internal thoracic artery for extended coronary bypass conduits. Ligation is required in some thoracoscopic approaches to the lower chest and when dividing the diaphragm for thoracoabdominal exposure.

Pathology

Common Injuries & Conditions

Musculophrenic Artery Injury in Port Placement

Trocar or port insertion at the subcostal margin without adequate visualization can lacerate the musculophrenic artery, causing significant haemorrhage requiring laparoscopic or open suture ligation for control.