In the present study, by evaluating the efficacy and safety of low intensity ultrasonic on ASO, to explore the noninvasive auxiliary treatment of ASO. 90 patients were randomly divided into 2 groups: A)control group, patients were given Conventional conservative treatment; B）treatment group, patients were given Conventional conservative treatment and low intensity ultrasonic treatment ; Treatments last for 4 weeks, three times a week, stimulation was given 8 minutes every time, location of treatment were lower limb ischemia area and its surrounding tissues; outcome indicators were recorded Before and 4 weeks after the trial, The Walking Impairment Questionnaire (WIQ), ankle brachial ratio, the farthest distance Walking, percutaneous tissue oxygen tension, tissue oxygenation index recovery time, local skin temperature, ultrasonic blood vessels, and muscle enzymes, hepatic and kidney function.

Ultrasound is a form of sound whose frequency is higher than the natural audible range for humans (> 20 kHz) and ultrasonography has been widely used as diagnostic devices for several decades. In addition to diagnostic purposes, ultrasound is clinically used for therapeutic applications, including tumor ablation, thrombolysis, bone regeneration, and facilitated drug delivery. Recently, therapeutic angiogenic effects of low-intensity ultrasound have been reported in endothelial cells, chick chorioallantoic membrane, and a rat model of hind limb ischemia. the investigators hypothesis low-intensity ultrasound can improve the ailment of ASO. In the present study, by evaluating the efficacy and safety of low intensity ultrasonic on ASO, to explore the noninvasive auxiliary treatment of ASO. 90 patients were randomly divided into 2 groups: A)control group，patients were given Conventional conservative treatment: B）treatment group，patients were given Conventional conservative treatment and low intensity ultrasonic treatment; Treatments last for 4 weeks, three times a week, stimulation was given 8 minutes every time, location of treatment were lower limb ischemia area and its surrounding tissues；outcome indicators were recorded Before and 4 weeks after the trial, The Walking Impairment Questionnaire (WIQ), ankle brachial ratio, the farthest distance Walking, percutaneous tissue oxygen tension, tissue oxygenation index recovery time, local skin temperature, ultrasonic blood vessels, and muscle enzymes, hepatic and kidney function.

the investigators speculate after 4 weeks of Low intensity ultrasonic treatment, all the observation index of ASO patients can be improved; meanwhile, creatine kinase, liver and kidney function, blood in urine routine, electrocardiogram (ecg) has no obvious change.

Inclusion Criteria:

• lower limb arteriosclerosis occlusion disorder patients
• In line with the Fontaine II - Ⅲ period clinical stage
• Aged 35 to 70 years old
• No major organ dysfunction, including heart, liver and kidney
• Can understand the procedures and methods of the test, strictly observe clinical trial plan to complete the test, and sign the informed consent

Exclusion Criteria:

• Fontaine clinical staging in patients with stage I
• Aged under 35 or more than 70 - year - old patient
• Women with pregnancy or lactation
• Childless and one year plan pregnancy
• Patients with cardiac pacemaker
• Patients with malignant tumor, psychosis
• Accompanied by severe heart, brain, kidney and hematopoietic system disease
• The following appeared in the process of being test: myocardial infarction, severe/unstable angina, coronary artery/peripheral artery bypass grafts, heart failure, cerebrovascular accident (including transient ischemic attack); And epilepsy, severe liver and kidney function is not complete, mechanical intestinal obstruction, bradycardia, bronchial asthma and other diseases
• Researchers think the patient has any problem that may cause the participants can't finish this research ，or any other situation of risk to participants