One cause of painful veins in the hands is Buerger's disease, which typically affects small- and medium-sized arteries and veins, states WebMD. Blocked arm and leg arteries reduce blood flow to the fingers and hands, causing pain even when resting. As of 2015, doctors don't know what causes the blockage.
A strong link exists between using or being exposed to tobacco, and developing blocked arteries, notes WebMD. When significant blockages occur, gangrene may set in, mandating amputation of a patient's fingers. Patients with Buerger's disease typically experience inflamed veins and symptoms of Raynaud's phenomenon, such as cold, numb, discolored fingers and spasms of small arteries.