Ulnar vein
The ulnar vein is one of the two major deep veins of the forearm, along with the radial vein. As is usual in the upper and lower limbs, there are often two veins (venae comitantes) that run on either side of the ulnar artery and anastomose freely with each other.
It forms in the hand from the deep palmar venous arch. As it ascends in the medial aspect of the anterior compartment of the forearm, it receives numerous tributaries that accompany the respective branches of the ulnar artery. The ulnar vein terminates in the cubital fossa where it joins the radial vein to form the brachial vein.
The ulnar vein drains the medial structures of the forearm, but little of the hand.