Browse by Audience
We pursued the hypothesis that complex regional pain syndrome (CRPS) signs observed by neurologic examination display a structure allowing for alignment of patients to particular phenotype clusters.
Adverse childhood experiences (ACEs) are common occurrences that are related to poor health outcomes, including chronic pain, in youth and adults. Research suggests that children of parents exposed to ACEs are also at risk of poor outcomes. However, little is known about the risk that ACEs confer for chronic pain across generations. Parent ACEs may play an important role in pediatric chronic pain, given their association with key parent factors (eg, mental and physical health).
Chronic postoperative pain affects approximately 20% of patients with knee osteoarthritis after total knee replacement. Circulating microRNAs can be found in serum and might act as biomarkers in a variety of diseases. The current study aimed to investigate the preoperative expression of circulating microRNAs as potential predictive biomarkers for the development of chronic postoperative pain in the year following total knee replacement.
To investigate whether TMD-related characteristics are indeed specific to TMD or whether they are also associated with other chronic overlapping pain conditions (COPCs).
Tetrodotoxin (TTX) is a highly specific voltage-gated sodium channel (VGSC) blocker in clinical evaluation as a peripheral-acting analgesic for chronic pain. This study presents the first published results of the safety including cardiac liability of TTX at therapeutic-relevant concentrations in twenty-five healthy adults. Randomized, double-blind, placebo-, and positive- (moxifloxacin) controlled study evaluated single ascending doses of 15 µg, 30 µg, and 45 µg TTX over 3 periods with a 7-day washout between each period. Subcutaneous injections of TTX were readily absorbed, reaching maximum plasma concentration (C) within 1.5 h. Both extent of exposure (AUC) and C increased in proportion to dose. No QT prolongation was identified by concentration-QTc analysis and the upper bounds of the two-sided 90% confidence interval of predicted maximum baseline and placebo corrected QTcF (ΔΔQTcF) value did not exceed 10 ms for all tetrodotoxin doses, thereby meeting the criteria of a negative QT study. Safety assessments showed no clinically relevant changes with values similar between all groups and no subject withdrawing due to adverse events. Paresthesia, oral-paresthesia, headache, dizziness, nausea, and myalgia were the most common TEAEs (overall occurrence ≥5%) in the TTX treatment groups. TTX doses investigated in this study are safe, well-tolerated, and lack proarrhythmic proclivity.
Temporomandibular disorder is a common musculoskeletal pain condition with development of chronic symptoms in 49% of patients. Although a number of biological factors have shown an association with chronic temporomandibular disorder in cross-sectional and case control studies, there are currently no biomarkers that can predict the development of chronic symptoms. The PREDICT study aims to undertake analytical validation of a novel peak alpha frequency (PAF) and corticomotor excitability (CME) biomarker signature using a human model of the transition to sustained myofascial temporomandibular pain (masseter intramuscular injection of nerve growth factor [NGF]). This article describes, a priori, the methods and analysis plan.
An American Academy of Orthopaedic Surgeons guideline recommends tramadol for patients with knee osteoarthritis, and an American College of Rheumatology guideline conditionally recommends tramadol as first-line therapy for patients with knee osteoarthritis, along with nonsteroidal anti-inflammatory drugs.
Inhibitory pain modulation has been reported to be deficient in adults across different types of chronic pain, including migraine. To determine if a similar phenomenon occurs in youth, we performed a quantitative sensory testing investigation in adolescents with migraine (N=19). These patients were compared to healthy adolescents with (Fam-His; N=20) or without (Healthy; N=29) a family history of migraine (e.g., first degree relative with migraine). Subjects were first familiarized with the stimuli and visual analog rating scales using graded noxious stimuli (0°C, 43-49°C range). These data were used to explore potential pain sensitivity differences between the groups. Pain inhibition was assessed by conditioned pain modulation (CPM), which used both suprathreshold heat pain (heat CPM) and pressure pain thresholds (pressure CPM) as the test stimuli before and during cold water immersion (8°C). In response to the graded heat stimuli Fam-His participants reported higher pain intensity ratings compared to migraine patients, who in turn, reported higher pain intensity ratings than the healthy controls [F=3.6, (df=2, 459), p=0.027]. For heat- and pressure- CPM, there was no significant group difference in the magnitude of CPM responses. Thus, adolescents with migraine and healthy adolescents have similar inhibitory pain modulation capability despite having marked differences in pain sensitivity. Although Fam-His participants are asymptomatic, they demonstrate alterations in pain processing which may serve as markers for prediction of migraine development.
Little is still known about the underlying mechanisms that drive and maintain neuropathic pain (NeuP). Recently, lipids have been implicated as endogenous proalgesic ligands affecting onset and maintenance of pain; however, in the case of NeuP, the relationship is largely unexplored.
Central sensitization (CS) involves dysfunctional central nervous system pain modulation resulting in heightened pain perception. Central sensitization is not commonly assessed among patients with opioid use disorder (OUD), despite the fact that pain has been implicated in the development, maintenance, and relapse of OUD and chronic opioid use may produce opioid-induced hyperalgesia. Central sensitization is a plausibly important mechanism underlying the complex relationship between OUD and chronic pain. However, this premise is largely untested.