Acupuncture relieves knee pain. Maternal and Child Health Hospital of Zhoushan City researchers investigated the effectiveness of electroacupuncture and moxibustion for the treatment of knee osteoarthritis. Patients receiving electroacupuncture had a 60% total effective rate and patients receiving manual acupuncture with moxibustion had a 48.89% total effective rate.

A closer look at the results demonstrates important clinical differences between electroacupuncture and moxibustion. Electroacupuncture had a higher rate of positive patient outcomes for relief of pain. Electroacupuncture also excelled at relief of knee stiffness in the morning. Electroacupuncture had a shorter duration of time between onset of treatment and relief of pain. Electroacupuncture outperformed moxibustion in the ability to restore daily living activities.

Manual acupuncture with moxibustion outperformed electroacupuncture in the time between onset of treatment and relief from knee stiffness with swelling. The results indicate that electroacupuncture and moxibustion have different clinical advantages. Moxibustion reduced swelling more readily while electroacupuncture provided a more significant analgesic effect.

The study involved randomization of ninety osteoarthritis patients into two groups, electroacupuncture and moxibustion. Acupuncture was applied with patients in a supine position. Acupuncture needles were 0.3 x 40 mm. Perpendicular insertion at local points was applied. Primary acupuncture points included:
Xuehai, SP10
Xiyan
Zusanli, ST36
Yinlingquan, SP9
Shenshu, BL23

Supplementary points were added to the protocolized acupuncture point prescription based on differential diagnostics. Sanyinjiao (SP6) was added for patients with continuous pain. Weizhong (BL40) was added for patients with severe pain intensity.

Electroacupuncture was applied at 5 Hz and the intensity level was set to patient tolerance levels. Warm needle acupuncture involved the attachment of moxa to the acupuncture needles. Both treatment regimens involved the same approach to the acupuncture point prescriptions and were administered three days per week for four consecutive weeks. The researchers note that each approach to acupuncture, both moxibustion and electroacupuncture, have their own strengths and limitations.

Xiong et al. took a slightly different approach to examining the effectiveness of acupuncture for the treatment of knee osteoarthritis. The researchers concluded that acupuncture combined with Tui-Na is effective for the resolution of knee pain and stiffness. In addition, the combined therapy is effective in the restoration of knee functionality.

Liu et al. found acupuncture highly effective for the treatment of knee osteoarthritis pain. Electroacupuncture at Xiyan was applied. The results indicated that deep needling of Xiyan produced significantly greater clinical results than shallow or moderate needle insertion. Supplementary points were also used in the investigation and included: Heding, GB34 (Yanglingquan), ST36 (Zusanli). Deep needling of Xiyan produced greater pain relief and reversal of leg flaccidity than shallow or moderate needle insertion.

Several biochemical mechanisms responsive to acupuncture needle stimulation may be responsible for the beneficial patient outcomes. The work of Morgana et al., published in Molecular Neurobiology, reveals that manual acupuncture stimulation downregulates M1 macrophage pro-inflammatory cells and upregulates M2 macrophage anti-inflammatory cells. This results in reductions of both pain and swelling. One reason for this response is that M2 macrophages are an important source of IL-10, interleukin-10. IL-10 is an anti-inflammatory cytokine, which in turn regulates actions between cells. Morgana et al. note, "These findings provide new evidence that MA (manual acupuncture) produces a phenotypic switch in macrophages and increases IL-10 concentrations in muscle to reduce pain and inflammation." This important discovery measures one of many biological responses to acupuncture that yields positive patient outcomes.

Zhang et al., whose work was published in Anesthesiology - The Journal of the American Society of Anesthesiologists, measured biological responses to electroacupuncture. Their research finds 2 to 10 Hz electroacupuncture more effective than 100 Hz electroacupuncture for pain relief and the reduction of inflammation. The researchers document that electroacupuncture "blocks pain by activating a variety of bioactive chemicals through peripheral, spinal, and supraspinal mechanisms." Specifically, they measured acupuncture’s ability to activate endogenous opioids and other biochemicals that desensitize pain sensory receptors, nociceptors. They note that electroacupuncture desensitizes "peripheral nociceptors and reduce(s) proinflammatory cytokines peripherally and in the spinal cord, and serotonin and norepinephrine, which decrease(s) spinal N-methyl-D-aspartate receptor subunit GluN1 phosphorylation."

The research teams of Zheng et al. and Morgana et al. demonstrate that acupuncture’s ability to regulate cytokines is integral to its ability to reduce pain and inflammation. Cytokines are immunoregulatory proteins secreted by cells. As research emerges, the bioactive properties of acupuncture are revealed and measured by scientists. The question of whether or not acupuncture works has fallen by the wayside. Now the question remains, what are the most significant biological mechanisms by which acupuncture exerts its effective action? Already, we know many of the answers.

References:
Zhou WC. (214). Clinical Comparative Study of Electro-acupuncture and Warm Acupuncture on Kidney Marrow Deficiency Syndrome of Knee Osteoarthritis. Journal of Emergency in Traditional Chinese Medicine. 23(8).

Chen L. (2013). Electroacupuncture combined with warm acupuncture in treating 67 cases of knee osteoarthritis. 8(2): 236 – 237.

Xiong XQ, Li FY & Qian JH. (2014). Acupuncture Combined with Chinese Massage in the Treatment of Knee Osteoarthritis. Journal of Clinical Acupuncture and Moxibustion. 30(6).

Liu, N. "Clinical Observations on Deep Needling of Points Dubi and Medial Xiyan for the Treatment of Knee Osteoarthritis." Shanghai Journal of Acupuncture and Moxibustion (2013): 857-858.

Morgana D., da Silva, Franciane Bobinski, Karina L. Sato, Sandra J. Kolker, Kathleen A. Sluka, and Adair RS Santos. "IL-10 Cytokine Released from M2 Macrophages Is Crucial for Analgesic and Anti-inflammatory Effects of Acupuncture in a Model of Inflammatory Muscle Pain." Molecular Neurobiology (2014): 1-13.