Objective To observe the effects of electroacupuncture on stair climbing ability in patients with knee osteoarthritis（KOA）. Methods A total of 36 KOA patients were randomly divided into electroacupuncture group and control group

with 18 cases in each group. Acupoints adopted in the electroacupuncture group were Yanglingquan（GB 34）

Yinlingquan（SP 9）

Xuehai（SP 10）

Liangqiu（ST 34）

Zusanli（ST 36）

Neixiyan（EXLE 4）

Dubi（ST 35）. The electroacupuncture group accepted electroacupuncture with a continuous square wave with a frequency of 2 Hz

and the current intensity depends on patient tolerance

for 30 min. The control group received shallow acupuncture about 2 cm next to the acupoints in the electroacupuncture group. They were connected with electroacupuncture instrument

but without current

and needle retention for 30 min. Both groups were treated for 3 weeks

totally 11 times. Stair climbing gait was measured before and after treatment. Velocities and other spatial-temporal parameters variability during ascending and descending stairs were analyzed. Results After treatment

velocities during both ascending and descending stairs in the electroacupuncture group were increased than those before treatment（P < 0. 01

P < 0. 05）. The coeffeicient of variation of gait cycle during stair descending on left limb decreased than those before treatment（P < 0. 05）. The coeffeicient of variation of step length and the initial double support time during stair ascending was decreased（P < 0. 05

P < 0. 01）. In the control group

the coeffeicient of variation of initial double support time and gait frequency during stair descending on right limb decreased significantly（P < 0. 01

P < 0. 05）. After treatment

the variation of swing time of stair descend on right lower limb in the electroacupuncture group was decreased compared with those of the control group（P < 0. 05）. There were no significant differences in the comparison of other indicators（P > 0. 05）. Conclusion Electroacupuncture may increase the velocities of stair ascending and descending in patients with KOA

also reduce the coeffeicient of variation of spatial-temporal parameters

improve the gait stability of stair ascending and descending

thus improving the ability of stair climbing.