The effectiveness of different acupuncture therapies for neck pain: A protocol for systematic review and/or network meta-analysis

Modulatory effects of acupuncture on raphe nucleus-related brain circuits in patients with chronic neck pain: A randomized neuroimaging trial

OBJECTIVE

Acupuncture has shown promise in treating neck pain. Clinical trials have shown mixed results, possibly due to heterogeneous methodologies and the lack of knowledge regarding underlying brain circuit mechanism of action. In this study, we investigated the specific contribution of the serotonergic system in treating neck pain, and the specific brain circuits involved.

METHODS

A total of 99 patients with chronic neck pain (CNP) were randomized to receive true acupuncture (TA) or sham acupuncture (SA) 3 times weekly for 4 weeks. Patients with CNP in each group were assessed for primary outcomes by measuring the Visual Analog Scale (VAS) and the duration of each attack; secondary outcomes were measured using the Neck Disability Index (NDI), Northwick Park Neck Pain Questionnaire (NPQ), McGill Pain Questionnaire (MPQ), Self-rating Anxiety Scale (SAS), Self-rating Depression Scale (SDS) and the 12-item Short Form Quality Life Scale (SF-12); levels of functional circuits connectivity were assessed using resting-state functional magnetic resonance imaging in the dorsal (DR) and median (MR) raphe nucleus, before and after undergoing acupuncture.

RESULTS

Patients receiving TA showed more extensive symptom improvement compared with SA. Regarding the primary outcomes, changes observed in the TA group were as follows: VAS = 16.9 mm (p < 0.001) and the duration of each attack = 4.30 h (p < 0.001); changes in the SA group: VAS = 5.41 mm (p = 0.138) and the duration of each attack = 2.06 h (p = 0.058). Regarding the secondary outcomes, changes in the TA group: NDI = 7.99 (p < 0.001), NPQ = 10.82 (p < 0.001), MPQ = 4.23 (p < 0.001), SAS = 5.82 (p < 0.001), SDS = 3.67 (p = 0.003), and SF-12 = 3.04 (p < 0.001); changes in the SA group: NDI = 2.97 (p = 0.138), NPQ = 5.24 (p = 0.035) and MPQ = 2.90 (p = 0.039), SAS = 1.48 (p = 0.433), SDS = 2.39 (p = 0.244), and SF-12 = 2.19 (p = 0.038). The modulatory effect of TA exhibited increased functional connectivity (FC) between the DR and thalamus, between the MR and parahippocampal gyrus, amygdala, and insula, with decreased FC between the DR and lingual gyrus and middle frontal gyrus, between the MR and middle frontal gyrus. Furthermore, changes in the DR-related circuit were specifically associated with the intensity and duration of pain, and the MR-related circuit was correlated with the quality of life with CNP.

CONCLUSION

These results demonstrated the effectiveness of TA in treating neck pain and suggested that it regulates CNP by reconfiguring the function of the raphe nucleus-related serotonergic system.

Comparative effectiveness of different acupuncture therapies for neck pain

BACKGROUND

Neck pain is a common musculoskeletal symptom that has negative effects on quality of life and work productivity. Acupuncture has been widely used for neck pain, and a number of randomized controlled trials (RCTs) and systematic reviews (SRs) have evaluated its effectiveness. However, previous studies have obtained inconsistent results regarding the effects of acupuncture for neck pain, and there is no SR for the comparative efficacy and safety of various types of acupuncture. Therefore, we herein conducted a SR and network meta-analysis to compare and rank different types of acupuncture with respect to their effectiveness in treating neck pain.

METHODS

We searched 9 electronic databases for relevant RCTs published from their inception to July 1, 2021. Pairwise meta-analyses and network meta-analysis were performed with R software using the frequentist framework. Change of pain intensity was assessed as the primary outcome, and change of pain-related disability and efficacy rate were assessed as secondary outcomes. The Cochrane risk of bias tool and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) instrument were used to evaluate the quality of the included RCTs and the certainty of the evidence.

RESULTS

A total of 65 RCTs involving 5266 participants and 9 interventions were included. Three network meta-analyses were constructed for the following: pain intensity (42 RCTs, 3158 participants), pain-related disability (21 RCTs, 1581 participants), and efficacy rate (40 RCTs, 3512 participants). The results indicated that fire acupuncture, electroacupuncture, and warm acupuncture were more effective than manual acupuncture in terms of pain intensity reduction and efficacy rate, and that electroacupuncture decreased pain-related disability more effectively than manual acupuncture. Fire acupuncture ranked first among the 9 interventions. The overall q of evidence was very low according to the GRADE assessment. The reported adverse events were not serious.

CONCLUSION

Fire acupuncture, warm acupuncture, acupoint catgut embedding, and electroacupuncture ranked higher than other interventions (usual care, sham acupuncture, no treatment) in reducing the pain and disability index scores and the efficacy rate. However, the included trials were evaluated as being of low quality; thus, we recommend additional well-designed RCTs with larger sample sizes to confirm these findings.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42021235274.