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Carpal Tunnel Syndrome (CTS) is an entrapment neuropathy of the median nerve that alters the organization of the brain's primary somatosensory cortex (S1), both structurally and functionally. Our prior research also demonstrated that electro-acupuncture (EA), both local and remote/distal to the wrist, but not sham acupuncture, improved S1 somatotopy and peripheral (median) nerve conduction. However, the mechanisms linking EA-evoked brain response during therapy with improved clinical outcomes are unknown. We investigated functional connectivity during both rest and sustained electro-acupuncture at baseline in healthy controls and CTS patients and after 8 weeks of acupuncture therapy (local, distal, or sham EA) in CTS patients. Six minutes of 3T BOLD fMRI data were collected at rest and during EA. Data were processed with FMRIPREP and FSL to generate maps of connectivity between the S1 hand region and the rest of the brain (z > 2.3, pFWE

Objective Carpal tunnel syndrome (CTS) is a common median nerve entrapment neuropathy characterized by pain, paresthesias, diminished peripheral nerve conduction velocity (NCV) and maladaptive functional brain neuroplasticity. We evaluated structural reorganization in brain gray matter (GM) and white matter (WM) and whether such plasticity is linked to altered median nerve function in CTS. Methods We performed NCV testing, T1-weighted structural MRI, and diffusion tensor imaging (DTI) in 28 CTS and 28 age-matched healthy controls (HC). Voxel-based morphometry (VBM) contrasted regional GM volume for CTS versus HC. Significant clusters were correlated with clinical metrics and served as seeds to define associated WM tracts using DTI data and probabilistic tractography. Within these WM tracts, fractional anisotropy (FA), axial (AD) and radial (RD) diffusivity were evaluated for group differences and correlations with clinical metrics. Results For CTS subjects, GM volume was significantly reduced in contralesional S1 (hand-area), pulvinar and frontal pole. GM volume in contralesional S1 correlated with median NCV. NCV was also correlated with RD and was negatively correlated with FA within U-fiber cortico-cortical association tracts identified from the contralesional S1 VBM seed. Conclusions Our study identified clear morphometric changes in the CTS brain. This central morphometric change is likely secondary to peripheral nerve pathology and altered somatosensory afference. Enhanced axonal coherence and myelination within cortico-cortical tracts connecting primary somatosensory and motor areas may accompany peripheral nerve deafferentation. As structural plasticity was correlated with NCV and not symptomatology, the former may be a better determinant of appropriate clinical intervention for CTS, including surgery., Highlights ► CTS demonstrated reduced GM volume in S1, pulvinar, and frontal pole. ► GM volume in S1 was significantly correlated with median nerve conduction velocity. ► Median nerve velocity was linked to WM microstructure in tracts connected to S1.

Chronic neuropathic pain is a prevalent problem that eludes cure and adequate treatment. The persistence of intense and aversive symptoms, inadequacy of available treatments, and impact of such pain on all aspects of functioning underscore the important role of several psychosocial factors in causing, maintaining, and amplifying the perception of pain severity, coping adequacy, adaptation, impaired physical function, and emotional distress responses. Moreover, these factors have an influential role in response to treatment recommendations. In this article, we (1) review the prevalence and nature of emotional distress, (2) describe and propose methods for screening and comprehensive psychosocial assessment, and (3) review evidence supporting the potential complementary role of psychosocial treatments of patients with chronic pain. The cognitive-behavioral perspective and treatment approach are emphasized because the greatest amount of evidence supports their benefits. Published results of psychological treatments are modest; however, the same indictment can be placed on currently available pharmacological, medical, and interventional treatments for patients with chronic pain. We note the limited research on the effectiveness of psychological treatment specifically applied to patients with chronic neuropathic pain but suggest that it is reasonable to extrapolate from successful trials in other types of chronic pain. Furthermore, psychological approaches should not be viewed as alternatives but rather should be integrated as part of a comprehensive approach to the treatment of patients with chronic neuropathic pain.

In summary, the past several years have shown an increase in the quality of trials examining the clinical efficacy of various CAM modalities for pain conditions. There is still need to raise the quality of the studies from a scientific and methodological point of view in many areas of CAM research by randomization, appropriate sample size, blinding, and developing more sophisticated sham procedures. However, much work still has to be done to find ways to preserve the clinical authenticity of CAM treatment methods when brought into the light of a research protocol. Recent attempts have been made to find a method of maintaining the standardization and reproducibility of research protocols while allowing the kind of flexible treatment that would normally be applied in a clinical setting. Other questions that should be answered with future studies include understanding how treatment length influences outcome, if maintenance treatments are needed for chronic conditions, and cost and risk comparisons with standard pharmacological treatment. Providing this kind of detail will assist both with reproducibility as well as help us gain a better understanding about whether certain treatment paradigms are superior to others for specific clinical conditions. Finally, physicians who have an interest in pursuing CAM research should educate themselves both about the methodological issues inherent with the particular area of interest as well as about ways to maintain the authenticity of the CAM treatment protocols so that the literature is not populated with more poorly designed studies. With the emerging interest in integrative medicine, there is a growing interest in collaboration and a greater number of physicians are interested in obtaining training in CAM modalities to help bridge this gap between CAM and conventional clinicians. For example, the American Academy of Medical Acupuncturists (AAMA) has been formed to help as both an educational and research forum for physician acupuncturists and the American Holistic Medical Association provides educational exposure in a broad range of Integrative and CAM modalities. The future of medicine will likely be Integrative and the more health care providers can educate themselves about this area of medicine, the better they will be able to provide the highest quality of care to their patients.