While we usually think of neuro-musculoskeletal structures for painful conditions there are clearly other factors that play a role. For example, with claudication calf or leg pain is due to Peripheral Arterial Disease (hardening of the arteries). Deep venous thrombosis (DVT) can also cause leg pain, but is due to blood clots in the veins ratherthen a neuro-musculoskeletal structure. Thoracic Outlet Syndrome occurs as a result of compression of the Subclavian artery or vein as they pass from the neck into the arm. It presents with complaints of arm pain, weakness and numbness, especially in the small and ring fingers.