[Comparison of pain thresholds of acupoints on the leg in healthy volunteers].

OBJECTIVE: To detect the pain threshold of acupoints on the leg in healthy volunteers so as to analyze the sensory specificity of different acupoints. METHODS: A total of 66 healthy volunteers (34 male and 30 female) aged from 19 to 64 years were recruited in the present study. Pain thresholds of acupoints on the lower leg were detected by using an Electronic Von Frey Anesthesiometer after constructing an anthropometric diagram about the cutaneous division of the lower leg. RESULTS: 1) Among acupoints Shugu (BL 65), Jinggu (BL 64), Kunlun (BL 60), Chengshan (BL 57) of the Bladder Meridian from the heel to the popliteal fossa, and non-acupoint (1cun lateral to BL 60), no significant differences were found among these acupoint regions in the pain threshold (P > 0.05), while that of the non-acupoint was significantly higher in comparison with these acupoint regions (P < 0.05). 2) At the Zusanli (ST 36) level, no significant differences were found among the Yanglingquan (GB 34), Zusanli (ST 36) and Yinlingquan (SP 9) regions in the pain threshold (P > 0.05) and the pain threshold was obviously higher in the non-acupoint (1 cun lateral to ST36) than in the GB34, ST36 and SP 9 regions (P < 0.05). 3) At the Xiajuxu (ST39) level, no significant differences were found among the Xiajuxu (ST39), Waiqiu (GB 36), Yangjiao (GB35), Feiyang (BL58) and Lougu (SP7) regions in the pain threshold (P > 0.05), but the non-acupoint (1 cun lateral to ST39) showed a higher threshold than those of the above-mentioned 5 acupoints (P < 0.05). 4) Among the 5 Xing-spring acupoints Dadu (SP2), Xingjian (LR2), Neiting (ST44) and Xiaxi (GB 43) distributing in the interdistal region, the pain threshold was lowest in the Neiting (ST 44) and highest in the Xiaxi (GB 43) regions (P < 0.05). 5) Among the acupoints Shuiquan (KI 5), Taixi (KI 3), Zhubin (KI 9) and Lougu (SP7) on the lower leg, the pain threshold was lowest in the Zhubin (KI 9) and highest in the Lougu (SP 7) regions (P < 0.05). CONCLUSION: In healthy subjects, the pain threshold is generally higher in the non-acupoint region and also shows a sparse lower sensory threshold in some acupoints as Neiting (ST 44), Zhubin (KI 9), etc. The specificity of acupoints needs being studied further.