Musculophrenic veins are paired vessels responsible for draining blood from the lower anterior intercostal spaces, the diaphragm, and regions of the anterior abdominal wall. These veins empty into the internal thoracic veins.
Musculophrenic veins arise from the convergence of veins in the lower anterior intercostal spaces and the superior diaphragm. Each vein runs obliquely along the costal margin, usually draining into the internal thoracic vein near the sixth costal cartilage.
Main tributaries include:
Musculophrenic veins collect blood from:
The musculophrenic veins accompany the musculophrenic arteries along the costal margin but drain into the internal thoracic veins instead of central veins.
Knowledge of the musculophrenic veins is important in surgical interventions related to the diaphragm, lower thoracic wall, or anterior abdominal wall. Awareness of their pathway reduces risk during imaging or surgery.