- Three factors combine to promote tissue necrosis in diabetic feet: ischemia, neuropathy and trauma. Among them, ischemia peripheral arterial disease may play the important roles in the development of DFU. Moreover, diffuse vascular disease is the main characteristics, and thus it becomes difficult for treatment by using arterial bypass or balloon angioplasty. Therefore, we hypothesized that continuous arterial thrombolysis may be an effective therapy in diabetic foot. The purpose of this study is to investigate the effectiveness and safety of continuous intra-femoral artery injection of urokinase by micro-artery-pump in diabetic ulcers.