Dorsal Branches of the Posterior Intercostal Veins, Posterior View

Description

Posterior thoracic anatomy is centered on the vertebral column and adjacent ribs, with the dorsal branches of the posterior intercostal veins running in each intercostal space near the costotransverse joints. Blue venous channels course posteriorly from the intercostal spaces to the deep paraspinal region, then divide into medial and lateral dorsal branches that track inferior and lateral over the intrinsic back muscles toward the skin and posterior shoulder girdle. Spinous processes and laminae provide the midline reference, while the ribs sweep laterally toward the scapulae and proximal humeri, framing the segmental pattern of the thoracic venous drainage. Segmental dorsal venous anatomy matters because it sits at the crossroads of the thoracic wall, the posterior vertebral elements, and the valveless vertebral venous plexus. In posterior approaches to the thoracic spine, including laminectomy and pedicle screw placement, these veins and their communications can be a source of persistent bleeding when the fascia over the paraspinal muscles is elevated or when the costotransverse region is exposed. The same connections help explain how infection or metastasis may spread through Batson’s plexus to vertebral bodies without passing through the lungs. Bleeding here is often diffuse. Use this artwork in gross anatomy and regional thorax teaching to reinforce intercostal space orientation, dorsal ramus territory, and the relationship of posterior intercostal veins to ribs, vertebrae, and scapular landmarks. It also fits spine surgery atlases and radiology education when correlating posterior thoracic wall venous pathways with CT or MR images in the paraspinal compartment. Anatomical accuracy verified by SciePro's Medical Advisory Board.