Acupuncture Enhances Signalsat Sensitized Acupoints to Elevate Pressure Pain Thresholdin Knee Osteoarthritis Patients

Objective:To observe the pressure pain threshold(PPT),skin conductance(SC)and blood perfusion(BP)of the sensitized acupoints in patients with knee osteoarthritis(KOA),and explore the mechanism of acupuncture at the sensitized acupoints for treating diseases.Methods:Eleven healthy subjects and 11 unilateral KOA patients were recruited from July 2020 to March 2021 in this study.The PPT,SC and BP of control acupoints in healthy controls,and non-sensitized and sensitized acupoints in KOA patients were measured and compared between baseline and after manual acupuncture(MA)treatment.Results:Before MA treatment,lower PPT was observed at the sensitized acupoints comparedwith non-sensitized andcontrol acupoints(P<0.05).After MA treatment,PPT at the sensitized acupoints increased significantly in KOA patients(P<0.05).Before MA treatment,there was no statistical difference in SC and BP among control,non-sensitized and sensitized acupoints(P>0.05).Compared with the control and non-sensitized acupoints,there were significant increases of SC and BP in sensitized acupoints of KOA patients after MA treatment(P<0.05 or P<0.01).Conclusion:MA at sensitized acupoints could elevate PPT of KOA patients,which may be associated with the increment of SC and BP.