To explore the clinical effects of abdominal acupuncture combined with warm needling on knee osteoarthritis (KOA).
Eighty-six patients with KOA were divided into a treatment group and a control group according to the digital random table, 43 cases in each one. In the treatment group, patients were treated with abdominal acupuncture at Zhongwan (CV 12), Guanyuan (CV 4) and Huaroumen (ST 24), Wailing (ST 26) and Xiafengshidian (Extra) on the affected side, as well as warm needling at Neixiyan (EX-LE 4), Dubi (ST 35), Heding (EX-LE 2), Liangqiu (ST 34) and Xuehai (SP 10) of the affected side. In the control group, warm needling was given. All the patients were treated 5 times a week for 4 weeks. Each dimension score of Western Ontario and McMaster University (WOMAC) osteoarthritis index scale and health survey 36-item short form (SF-36) of the two groups was compared before and after treatment. Enzyme-linked immunosorbent assay was applied to test serum vascular endothelial growth factor (VEGF) and angiopoietin-1(Ang-1).
Compared with those before treatment, the scores of pain, stiffness, joint function of WOMAC scale and serum VEGF, Ang-1 of the two groups were lower after treatment (all 
Abdominal acupuncture combined with warm needling can effectively alleviate pain and stiffness, improve the function of knee joint and quality of life, with definite effect for KOA. The mechanism may be related to the decreasing of serum VEGF and Ang-1.