Possible role of the internal vertebral venous plexus during exercise in humans

The internal vertebral venous plexus (IVVP) is an extensive vascular network surrounding the spinal cord. However, little attention has been paid to its physiological role. During leg exercise, warm blood returns from the legs to the heart. If a portion of the blood is conveyed via the IVVP, it may warm the spinal cord and facilitate thermoregulatory responses. To assess this, we investigated how venous blood from the legs return to the body core. Direct contrast-enhanced magnetic resonance (MR) venography clearly demonstrated the anterior IVVP at the lumbar and thoracic regions in one subject after leg exercise, partially supporting our hypothesis.