Acupuncture for Lumbar Spinal Stenosis

Inclusion Criteria:

1. Meet the diagnosis criteria of LSS;
2. Aged between 50-80 years;
3. Neurogenic claudication (NC) for more than 3 months;
4. Able to walk for at least 20 meters continually without device assistance, and forcedto stopped walking out of NC within 30 mins in the meanwhile;
5. The average pain of buttocks and/or legs scores≥4 on the Numerical Rating Scale (NRS)when walking, standing, or extending the back in the past week;
6. More severe pain in the buttock and/or leg than in the lower back;
7. Score at least 7 on Modified Roland-Morris Disability Questionnaire（RMDQ）;
8. Central sagittal diameter stenosis of lumbar spinal canal as manifested by MRI or CTscan;
9. Volunteer to participate the trial and provide written informed consent.

Exclusion Criteria:

1. Non-degenerative LSS, such as congenital, post-traumatic or spondylolisthesis LSS;operation indications, such as segmental muscular atrophy, bowel and bladderdisfunction, and spinal instability; tuberculosis or tumor in the lumbar area; ormultiple vertebral compression fracture or compression fracture in the segment ofstenosis;
2. Vascular claudication;
3. Severe heart, pulmonary, liver and/or kidney diseases;
4. Clinical comorbidities that may interfere with the assessment of pain intensity orwalking ability, such as fibromyalgia, chronic widespread pain, amputation, stroke,Parkinson's disease, spinal cord injury, severe diabetes, and severe hypertension etc;
5. Unable to complete motorized treadmill test at the speed of 2km/h;
6. Severe psychiatric disorder or cognitive impairment that prevent the understanding ofthe outcome evaluating questionnaires;
7. A history of lumbar surgery;
8. Have received acupuncture treatments in the previous 2 weeks;