A cadaveric study of needle insertion at PC6 in eight wrists of four subjects and an understanding of the anatomy

Alternative pain management via endocannabinoids in the time of the opioid epidemic: Peripheral neuromodulation and pharmacological interventions

The use of opioids in pain management is hampered by the emergence of analgesic tolerance, which leads to increased dosing and side effects, both of which have contributed to the opioid epidemic. One promising potential approach to limit opioid analgesic tolerance is activating the endocannabinoid system in the CNS, via activation of CB1 receptors in the descending pain inhibitory pathway. In this review, we first discuss preclinical and clinical evidence revealing the potential of pharmacological activation of CB1 receptors in modulating opioid tolerance, including activation by phytocannabinoids, synthetic CB1 receptor agonists, endocannabinoid degradation enzyme inhibitors, and recently discovered positive allosteric modulators of CB1 receptors. On the other hand, as non-pharmacological pain relief is advocated by the US-NIH to combat the opioid epidemic, we also discuss contributions of peripheral neuromodulation, involving the electrostimulation of peripheral nerves, in addressing chronic pain and opioid tolerance. The involvement of supraspinal endocannabinoid systems in peripheral neuromodulation-induced analgesia is also discussed. LINKED ARTICLES: This article is part of a themed issue on Advances in Opioid Pharmacology at the Time of the Opioid Epidemic. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v180.7/issuetoc.

Changes in Acupuncture-Induced Specific Acupoint Neurotransmitters are Possibly Related to Their Physiological Functions in Rats

This study investigated changes in neurotransmitters induced by the application of electroacupuncture (EA) at Zusanli (ST36) and Neiguan (PC6). A total of 30 rats were divided into five groups: sham, ST (EA at bilateral ST36 and ST37), ScT (ST plus previous neurectomy of the bilateral sciatic nerves), ScS (sham plus previous neurectomy of the bilateral sciatic nerve), and PC (EA at bilateral PC6 and PC7). The P2X2 receptor expression was stronger in the sham group than in the ST and PC groups (both p < 0.05) but similar between the sham and ScT groups (p > 0.05). Dopamine levels in the extracellular fluid surrounding the acupoints were higher in the PC group than in the sham and ST groups during the postacupuncture period (both p < 0.05). Glutamate levels in the extracellular fluid surrounding the acupoints were higher in the ST group than in the sham group during the acupuncture period (p < 0.05) and higher in the ST group than in the sham and PC groups during the postacupuncture period (both p < 0.05). Serum adrenaline and noradrenaline levels were higher in the PC group than in the sham, ST, and ScT groups (all p < 0.05). Glutamate levels in the CSF were higher in the ST group than in the sham, ScS, and PC groups (all p < 0.05). GABA levels in the CSF were higher in the ST group than in the sham, ScT, and PC groups (all p < 0.05). EA at ST36 and ST37 and PC6 and PC7 exerted an analgesic effect, EA at PC6 and PC7 can enhance heart function, and EA at ST36 and ST37 modulates the cerebral cortex. However, the study needs an evaluation of direct pain behavior, heart function, and brain function in the future.

Restoring the Autonomic Balance in an Atrial Fibrillation Rat Model by Electroacupuncture at the Neiguan Point

OBJECTIVES

Autonomic nervous activity imbalance plays an important role in atrial fibrillation (AF). AF can be treated by acupuncture at the Neiguan point (PC6), but the mechanism remains elusive. Here, we investigated autonomic nervous system activity in electroacupuncture (EA) at PC6 in a rat AF model.

MATERIAL AND METHODS

In this study, we established a rat AF model via tail vein injection with ACh-CaCl2 for ten consecutive days with or without EA at PC6. AF inducibility and heart rate variability (HRV) were assessed by electrocardiogram. Next, we completed in vivo recording of the activity of cervical sympathetic and vagal nerves, respectively. Finally, the activities of brain regions related to autonomic nerve regulation were assessed by c-Fos immunofluorescence and multichannel recording.

RESULTS

EA at PC6 decreased AF inducibility and prevented changes in HRV caused by ACh-CaCl2 injection. Meanwhile, EA at PC6 reversed the increased sympathetic and decreased vagal nerve activity in AF rats. Furthermore, EA treatment downregulated increased c-Fos expression in brain regions, including paraventricular nucleus, rostral ventrolateral medulla, and dorsal motor nucleus of the vagus in AF, while c-Fos expression in nucleus ambiguus was upregulated with EA.

CONCLUSION

The protective effect of EA at PC6 on AF is associated with balance between sympathetic and vagal nerve activities.

Using magnetic resonance imaging to measure the depth of acupotomy points in the lumbar spine: A retrospective study

Background

The acupotomy is an acupuncture device recently used to stimulate lumbar vertebrae such as transverse processes (TPs) and facet joints (FJs). However, there are many organs, nerves, and blood vessels, which can lead to side effects if the needle misses the treatment target. Therefore, information regarding appropriate insertion depths, which is currently lacking, could facilitate its safe use. We retrospectively investigated the depth from the skin to the TP and FJ of the lumbar vertebrae, using magnetic resonance imaging (MRI).

Methods

This retrospective chart review was conducted at a single medical centre in Korea. From 55,129 patient records, 158 subjects were selected. Perpendicular depth from the skin to the left and right TPs and FJs was measured using T1-weighted sagittal plane MRI. Depth differences between the left and right sides were evaluated using the paired t-test and analysis of covariance (body mass index [BMI] as a covariate). The influence of BMI on depth at each location was evaluated by simple linear regression analysis.

Results

The mean age was 43.2 years and mean BMI was 23.6 kg/m². The depth from skin to the TPs or FJs was unaffected by age, sex, or side. Mean depths (cm) were as follows: (TPs) L1 = 4.5, L2 = 4.9, L3 = 5.3, L4 = 5.7, L5 = 5.9; (FJs) L12 = 3.8, L23 = 4.0, L34 = 4.4, L45 = 4.6, L5S1 = 4.6. Depth was highly correlated with BMI at each location.

Conclusion

The depth of TPs and FJs adjusted for BMI can safely and effectively be used for treatment via various invasive interventions, including acupotomy treatment, in the lumbar region.

Local effects of acupuncture on the median and ulnar nerves in patients with carpal tunnel syndrome: a pilot mechanistic study protocol

Background

While acupuncture’s mechanism of action is not fully understood, there is consensus that the nervous system plays a key role in processing its effects. This research is based on the structural theory of acupuncture, which aims to correlate the location of acupuncture points to peripheral nerves, spinal segments, and spinal plexuses. This mechanistic study explores the close anatomical association between the Pericardium meridian/median nerve and the Heart meridian/ulnar nerve in an attempt to produce electrophysiologic data measuring acupuncture’s direct, nerve-specific effect on the underlying nerves. Specifically, the purpose of this research is to use nerve conduction studies (NCSs) and quantitative sensory testing (QST) to assess for any local, nerve-specific effect of three acupuncture modalities on two anatomically distinct nerves in the forearm — the median and ulnar nerves — in subjects with carpal tunnel syndrome (CTS). The choice of CTS as an injured nerve model allows for comparisons between the response in an injured nerve (median) to that of a healthy one (ulnar).

Methods

Subjects with mild to moderate CTS will be randomized to three intervention groups: manual acupuncture and low- and high-frequency electroacupuncture. Each subject will receive two treatments, 1 week apart, to points in the forearm, which overlay the median nerve (Pericardium meridian) or the ulnar nerve (Heart meridian). Acupuncture will be administered in random order to minimize learning effects in sensory testing. During Week 1, baseline NCS and QST (vibration and cold detection thresholds) will be obtained in both nerve territories, followed by acupuncture and post-acupuncture NCS and QST measurements in both nerve territories. During Week 2, repeat baseline QST and NCS measurements will be obtained, followed by acupuncture to points overlying the nerve not treated in Week 1, followed by post-acupuncture NCS and QST measurements in both nerve distributions.

Discussion

This works aims to capture and characterize the local effects of acupuncture on an underlying nerve and compare them to those on a neighboring nerve. Quantifying acupuncture’s effects using physiologic parameters and discrete values could standardize treatment regimens and help assess their therapeutic effect.

Trial registration

ClinicalTrials.gov, NCT03036657. Registered on 30 January 2017. Retrospectively registered.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-3094-5) contains supplementary material, which is available to authorized users.

The Case for Local Needling in Successful Randomized Controlled Trials of Peripheral Neuropathy: A Follow-Up Systematic Review

Objectives: This work follows-up on a systematic review, published in 2017, of acupuncture for the treatment of mono- and polyneuropathy and associated symptoms. Previously reviewed trials of acupuncture for neuropathy primarily used acupuncture points in close proximity to underlying nerves. Further exploration of point selection for the treatment of each neuropathic condition is needed to assess the anatomical relationships between acupuncture points and peripheral nerves with respect to the treatment of neuropathy. Methods: The 13 randomized controlled trials included in the original review studied acupuncture for neuropathy caused by diabetes, Bell's palsy, carpal tunnel syndrome (CTS), human immunodeficiency virus (HIV), and idiopathic causes. The present review reexamines all acupuncture points used, focusing on specific neuropathic condition treated. Anatomical diagrams are presented to highlight acupuncture points underlying the nerves' anatomical relationships. Each selected acupuncture point is reviewed in detail, including its Traditional Chinese Medicine theory-based function, the point's indications for use, and the peripheral nerve most closely associated with it. Results: In Bell's palsy, the majority of selected acupuncture points were associated with the ipsilateral facial nerve. In CTS, the majority of the selected acupuncture points were closely associated with the median nerve and its branches. In polyneuropathy caused by diabetes, HIV, or idiopathic causes, most selected acupuncture points were in close proximity to peripheral nerves. Conclusions: All reviewed trials of acupuncture for neuropathy and neuropathic pain use acupuncture points that are closely associated with the peripheral nerves treated. Local needling is crucial for successful treatment of peripheral neuropathy.

An exploration of the needling depth in acupuncture: the safe needling depth and the needling depth of clinical efficacy

Objective. To explore the existing scientific information regarding safe needling depth of acupuncture points and the needling depth of clinical efficacy. Methods. We searched the PubMed, EMBASE, Cochrane, Allied and Complementary Medicine (AMED), The National Center for Complementary and Alternative Medicine (NCCAM), and China National Knowledge Infrastructure (CNKI) databases to identify relevant monographs and related references from 1991 to 2013. Chinese journals and theses/dissertations were hand searched. Results. 47 studies were recruited and divided into 6 groups by measuring tools, that is, MRI, in vivo evaluation, CT, ultrasound, dissected specimen of cadavers, and another group with clinical efficacy. Each research was analyzed for study design, definition of safe depth, and factors that would affect the measured depths. Depths of clinical efficacy were discussed from the perspective of de-qi and other clinical observations. Conclusions. Great inconsistency in depth of each point measured from different subject groups and tools exists. The definition of safe depth should be established through standardization. There is also lack of researches to compare the clinical efficacy. A well-designed clinical trial selecting proper measuring tools to decide the actual and advisable needling depth for each point, to avoid adverse effects or complications and promote optimal clinical efficacy, is a top priority.

Proposed catalog of the neuroanatomy and the stratified anatomy for the 361 acupuncture points of 14 channels

BACKGROUND

In spite of the extensive research on acupuncture mechanisms, no comprehensive and systematic peer-reviewed reference list of the stratified anatomical and the neuroanatomical features of all 361 acupuncture points exists. This study creates a reference list of the neuroanatomy and the stratified anatomy for each of the 361 acupuncture points on the 14 classical channels and for 34 extra points.

METHODS

Each acupuncture point was individually assessed to relate the point's location to anatomical and neuroanatomical features. The design of the catalogue is intended to be useful for any style of acupuncture or Oriental medicine treatment modality. The stratified anatomy was divided into shallow, intermediate and deep insertion. A separate stratified anatomy was presented for different needle angles and directions.

RESULTS

The following are identified for each point: additional specifications for point location, the stratified anatomy, motor innervation, cutaneous nerve and sensory innervation, dermatomes, Langer's lines, and somatotopic organization in the primary sensory and motor cortices. Acupuncture points for each muscle, dermatome and myotome are also reported.

CONCLUSION

This reference list can aid clinicians, practitioners and researchers in furthering the understanding and accurate practice of acupuncture. Additional research on the anatomical variability around acupuncture points, the frequency of needle contact with an anatomical structure in a clinical setting, and conformational imaging should be done to verify this catalogue.