The ulnar artery supplies blood to the hand. It is a branch of the brachial artery. Among the branches of the ulnar artery are two interosseous arteries which arise either side of the interosseous membrane and supply the deep tissue between the radius and ulna. At the wrist, the ulnar artery lies lateral to the pisiform bone before dividing into superficial and deep branches.
The superficial branch anastomoses with the superficial branch of the radial artery to form the superficial palmar arch at the level of the distal border of the outstretched thumb.
The deep branch of the ulnar artery anastamoses with the deep branch of the radial artery to form the deep palmar arch.