[Effect of electroacupuncture on chronic pain in patients with knee osteoarthritis and its influence on central sensitization]

Key Findings

To observe the clinical therapeutic effect of electroacupuncture (EA) on chronic pain in patients with knee osteoarthritis (KOA) and to investigate its influence on serum biomarkers related to central sensitization. Ninety patients with chronic pain caused by KOA were randomly assigned to an EA group (45 cases, 3 cases dropped out) and a sham-EA group (45 cases, 5 cases dropped out and 1 case was eliminated). The patients in both groups received health education. Additionally, in the EA group, EA was performed at the acupoints such as Neixiyan (EX-LE4), Dubi (ST35), Heding (EX-LE2) and Xuehai (SP10) on the affected side, with dense-disperse wave, at the frequency of 2 Hz/100 Hz and the electric current of 1 mA to 2 mA, it was operated for 30 min in each session, once daily, 6 sessions a week, and for 4 consecutive weeks. In the sham-EA group, sham-EA was operated at the same acupoints as the EA group, with the same duration of interventions, but without electric stimulation exerted. In the baseline (week 0), and week 2, 4, 8 and 16, the score on numerical rating scale (NRS) for pain at rest and during activity, as well as pressure pain thresholds (PPTs) at the local and distal of knee joint were observed in the two groups separately. In week 0, 4, and 16, the Western Ontario and McMaster universities osteoarthritis index (WOMAC) and the 12-item short form health survey (SF-12) were scored. In week 0 and 4, the score on central sensitization inventory (CSI) and the levels of serum biomarkers related to central sensitization, such as glutamate (Glu), glutamine (Gln), substance P (SP), and calcitonin gene-related peptide (CGRP) were observed in the two groups. Compared with the baseline, the EA group showed the decrease in NRS scores at rest and during activity in week 2, 4, 8, and 16, in the scores on subscales and the total score of WOMAC in week 4 and 16, as well as in CSI score and serum levels of Glu, Gln, SP, and CGRP in week 4 (P<0.05); and presented higher PPTs at the local and distal knee joint in week 2, 4, 8 and 16 and the scores on physical and mental health of SF-12 in weeks 4 and 16 (P<0.05). The sham-EA group presented the reduced resting-related NRS scores in week 2, 4, and 8, the activity-related NRS score in week 4, the scores on pain and function subscales and the total score of WOMAC in week 4 and 16, and serum CGRP level in week 4 when compared with the baseline, separately (P<0.05); and PPTs at the center of knee point in week 2 and 4 and the lateral side in week 4 increased (P<0.05). After treatment and at each time point of follow-up visit, NRS scores at rest and during activity, the scores on each subscale and the total score of WOMAC, the score of CSI and serum levels of Glu, Gln, SP, and CGRP in the EA group were lower than those in the sham-EA group (P<0.05); PPTs at each site (except at the lateral side of knee point in week 2 and the deltoid point in week 16) and the scores of SF-12 (except mental health score of SF-12 in week 16) were higher in the EA group when compared with the sham-EA group (P<0.05). Change scores of NRS at rest and during activity were positively correlated with those of CSI in the EA group (P<0.05). Electroacupuncture effectively alleviates chronic pain of KOA, improves joint function and quality of life, which may be achieved through the inhibition of central sensitization. 目的：观察电针治疗膝关节骨关节炎（KOA）慢性疼痛患者的临床疗效及对中枢敏化相关血清标志物的影响。 方法：将90例KOA慢性疼痛患者随机分为电针组（45例，脱落3例）和假电针组（45例，脱落5例，剔除1例）。两组均接受健康宣教，电针组取患侧内膝眼、犊鼻、鹤顶、血海等穴进行电针干预，予疏密波，频率2 Hz/100 Hz，电流1～2 mA，每次治疗30 min，每天1次，每周6次，连续治疗4周；假电针组予相同穴位与疗程的假电针治疗。以基线期为第0周（治疗前），分别于第0、2、4、8、16周观察两组患者静息与活动时疼痛数字评分法（NRS）评分、膝关节局部和远端部位压痛阈值（PPTs）；于第0、4、16周观察两组患者西安大略和麦克马斯特大学骨关节炎指数（WOMAC）评分、SF-12健康调查简表（SF-12）评分；于第0、4周观察两组患者中枢敏化量表（CSI）评分及中枢敏化相关血清标志物[谷氨酸（Glu）、谷氨酰胺（Gln）、P物质（SP）、降钙素基因相关肽（CGRP）]水平。 结果：与治疗前比较，电针组患者第2、4、8、16周后静息和活动时NRS评分，第4、16周后WOMAC分项评分和总分，第4周后CSI评分及血清Glu、Gln、SP、CGRP水平均降低（P<0.05），第2、4、8、16周后膝关节局部和远端部位PPTs及第4、16周后SF-12身体健康、心理健康评分均升高（P<0.05）。与治疗前比较，假电针组患者第2、4、8周后静息NRS评分和第4周后活动时NRS评分，第4、16周后WOMAC疼痛、功能评分和总分及第4周后血清CGRP水平均降低（P<0.05），第2、4周后膝中心点PPTs及第4周后膝外侧点PPTs升高（P<0.05）。治疗后及随访时各时间点，电针组静息和活动时NRS评分、WOMAC分项评分和总分、CSI评分及血清Glu、Gln、SP、CGRP水平均低于假电针组（P<0.05），各部位PPTs（除第2周后膝外侧点PPTs和第16周后三角肌点PPTs）及SF-12评分（除第16周后心理健康评分）均高于假电针组（P<0.05）。电针组静息及活动时NRS评分变化值与CSI评分变化值呈正相关（P<0.05）。 结论：电针疗法可有效缓解KOA慢性疼痛、改善关节功能并提高生活质量，其机制可能与抑制中枢敏化相关。.

Why This Matters for Body-Mind Practice

[Draft — editorial context needed]

Source

• [[Effect of electroacupuncture on chronic pain in patients with knee osteoarthritis and its influence on central sensitization].](https://pubmed.ncbi.nlm.nih.gov/42443077/) — Zhongguo zhen jiu = Chinese acupuncture & moxibustion