Activity

The pathophysiology of pain in neuropathy is complex and may be linked to sensory phenotypes. Quantitative sensory testing, a standardized method to evaluate sensory profiles in response to defined stimuli, assesses functional integrity of small and large nerve fiber afferents and central somatosensory pathways. It has revealed detailed insights into mechanisms of neuropathy, yet it remains unclear if pain directly affects sensory profiles. The main objective of this study was to investigate sensory profiles in patients with various neuropathic conditions, including polyneuropathy, mononeuropathy, and lesions to the central nervous system, in relation to self-reported presence or absence of pain and pain sensitivity using the Pain Sensitivity Questionnaire. A total of 443 patients (332 painful and 111 painless) and 112 healthy participants were investigated. Overall, loss of sensation was equally prevalent in patients with and without spontaneous pain. Pain thresholds were equally lowered in both patient gras hyperalgesia was more frequent in painful mononeuropathy (compared with painless conditions). Self-reported pain sensitivity was significantly higher in painful than in painless neuropathic conditions. Our results reveal the presence of hyperalgesia and allodynia in patients with central and peripheral lesions of the somatosensory system not reporting spontaneous pain. This shows that symptoms and signs of hypersensitivity may not necessarily coincide and that painful and painless neuropathic conditions may mechanistically blend into one another.

Phantom limb pain (PLP) accounts for a significant reduction in quality of life and is difficult to treat. Prosthesis use has been shown to negatively covary with PLP. Recent research on body perception in amputees suggest that prosthesis ownership, defined as the extent to which a prosthesis is experienced as being part of the body rather than an artificial device foreign to the body, might interact with PLP. We used survey data from 2383 unilateral prosthesis-using upper-limb or lower-limb amputees and performed regression analyses to determine the relationship between prosthesis ownership and PLP. To test for specificity, we examined the role of prosthesis ownership also for residual limb pain (RLP) and nonpainful phantom limb sensations (npPLS). Prosthesis ownership was reduced in older participants and higher in lower-limb compared to upper-limb amputees. A longer residual limb and more frequent prosthesis use as well as a longer time since amputation also yielded higher values. Prostheses based on nato the interplay of body- and pain-related sensations after amputation, and could help to develop new treatment approaches for both PLP and RLP.This brief review provides a summary of existing research on virtual reality (VR) applications to pain. selleck products We distinguish three categories of studies – VR applications to clinical acute pain, chronic pain, and acute experimental pain, which are currently equally represented in the literature. The review highlights specific advancements in VR pain research as well as areas in need of more development in scrutiny. In particular, we note the pressing need for theoretical scaffolding to facilitate replicable, theoretically-driven methodology, communication, and advancements across the field. To that end, we provide a preliminary heuristic model of VR application to pain experience. The model distinguishes three categories of factors inherent in VR application to pain VR Configuration Factors, User Experiential Factors, and Pain Targets and Outcomes. VR Configuration Factors comprise technical input devices, system processes, and output devices, which present a virtual world to the user and enable User Experiential Factors of presence, interactivity, immersion, and embodiment. These interdependent experiential factors serve as potential mediators and moderators for subsequent changes in cognitive, emotional, social, behavioral, and physiological outcomes that serve as Targets of pain-related therapy. Given that rapid technological progress can both facilitate and frustrate research progress within the field, systematic, theoretically-informed inquiry into factors comprising and driving the effects of VR pain applications, combined with more rigorous theoretically-informed methodology, is a critical challenge.

Chronic neuropathic pain is frequently accompanied by memory impairment, yet the underlying mechanisms remain unclear. Here, we showed that mice displayed memory impairment starting at 14 days and lasting for at least 21 days after chronic constriction injury (CCI) of unilateral sciatic nerve in mice. Systemic administration of the pan histone deacetylase (HDAC) inhibitor sodium butyrate attenuated this memory impairment. More specifically, we found that hippocampus HDAC3 was involved in this process because the levels of its mRNA and protein increased significantly in the hippocampus at 14 and 21 days after CCI, but not sham surgery. Systemic administration of the selective HDAC3 antagonist RGFP966 attenuated CCI-induced memory impairment, improved hippocampal long-term potentiation impairment, and rescued reductions of dendritic spine density and synaptic plasticity-associated protein in the hippocampus. In addition, HDAC3 overexpression in the hippocampus led to memory impairment without affecting basal ated CCI-induced memory impairment, improved hippocampal long-term potentiation impairment, and rescued reductions of dendritic spine density and synaptic plasticity-associated protein in the hippocampus. In addition, HDAC3 overexpression in the hippocampus led to memory impairment without affecting basal nociceptive responses in naive mice. Our findings suggest that HDAC3 contributes to memory impairment after CCI by impairing synaptic plasticity in hippocampus. Histone deacetylase 3 might serve as a potential molecular target for therapeutic treatment of memory impairment under neuropathic pain conditions.

The STarT Back approach comprises subgrouping patients with low back pain (LBP) according to the risk of persistent LBP-related disability, with appropriate matched treatments. In a 12-month clinical trial and implementation study, this stratified care approach was clinically and cost-effective compared with usual, nonstratified care. Despite the chronic nature of LBP and associated economic burden, model-based economic evaluations in LBP are rare and have shortcomings. This study therefore produces a de novo decision model of this stratified care approach for LBP management to estimate the long-term cost-effectiveness and address methodological concerns in LBP modelling. A cost-utility analysis from the National Health Service perspective compared stratified care with usual care in patients consulting in primary care with nonspecific LBP. A Markov state-transition model was constructed where patient prognosis over 10 years was dependent on physical function achieved at 12 months. Data from the clinical trial and implementation study provided short-term model parameters, with extrapolation using 2 cohort studies of usual care in LBP.