Objective To observe the clinical efficacy and safety of Yaotongxiao Lotion（ 腰痛消洗剂） in the treatment of lumbar osteoarthritis with cold and dampness syndrome. Methods A randomized

double-blind

placebo-controlled clinical study was performed in 260 patients with lumbar osteoarthritis. Patients were randomly divided into an test group and a control group

with 130 patients in each group. The test group was given Yaotongxiao Lotion fumigation combined with traction. The control group was given placebo fumigation combined with traction

twice a day

for a total of 14 days. The changes of pain visual analogue scale（ VAS）

Oswestry dysfunction index（ ODI） and traditional Chinese medicine symptom scores were observed before treatment

7 days after treatment

14 days after treatment

and follow-up

and the clinical efficacy and adverse reactions were observed. Results There were 3 cases in the test group and 2 cases in the control group lost. After treatment

VAS of both groups decreased significantly. The difference before and after treatment as well as groups difference between groups at the same time were statistically significant（ P < 0. 05）. The ODI scores of both groups gradually decreased

but the improvement of ODI score was more significant in the test group after 7 days

14 days treatment and at the follow-up（ P < 0. 05）. The traditional Chinese medicine symptom scores of both groups were decreased

and the improvement was more obvious in the test group（ P < 0. 05）. The excellent and good rate of the test group and the control group was 68. 50% and59. 38% respectively. The test group was superior to the control group（ P < 0. 05）. Conclusion Yaotongxiao Lotion combined with traction therapy has a good clinical effect in the treatment of lumbar vertebrae osteoarthritis

which can significantly improve the lumbar motion of patients safely.