The Association of Pain Sensitization and Conditioned Pain Modulation to Pain Patterns in Knee Osteoarthritis

Abstract Background and aims The participation in ultra-marathons and other ultra-endurance events has increased exponentially over the past decade. There is insufficient data on variation in pain mechanisms in exercise overall but especially in the ultra-endurance athlete population. To further understand peripheral and central pain sensitization we have investigated pressure pain threshold and conditioned pain modulation during three separate ultra-marathon competitions. Methods Each ultra-marathon investigated was held in the state of Florida, USA, over flat, sandy and paved surfaces under generally warm to hot, humid conditions. Pressure pain threshold was measured utilizing a Baseline © Dolorimeter. The blunt end of the dolorimeter stylus was placed onto the distal dominant arm, equidistant between the distal radius and ulna, three times in a blinded manner to insure that the testing technician did not influence the subject’s responses. Conditioned pain modulation was measured immediately after the PPT measures by placing the non-dominant hand in a cool water bath maintained at 15°C. The same dolorimeter measurement was repeated two more times on the dominant arm while the non-dominant hand remained in the water. Data was analyzed with a paired t-test. Results Pressure pain threshold was significantly decreased (p<0.05) at 25, 50 and 100 miles. Conditioned pain modulation was also significantly decreased (p<0.05) at 25, 50 and 100 miles of an ultra-marathon competition. Conclusions Together these data suggest an increased peripheral and/or central pain sensitization starting at 25 miles and continuing throughout an ultra-marathon competition run in these conditions. This is the first study that provides evidence of a decreased peripheral pain threshold and decreased central pain inhibition from ultra-marathon running. Decreases in both the peripheral pain threshold and central inhibition may result from nociceptor plasticity, central sensitization or a combination of both. Implications Based on previous research that has indicated a central sensitization resulting from inflammation and the well-documented inflammatory response to the rigors of ultra-marathon competition, we suggest the decreased peripheral pain threshold and decreased descending pain inhibition results from this inflammatory response of running an ultra-marathon.

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The effect of one dry needling session on pain, central pain processing, muscle co-contraction and gait characteristics in patients with knee osteoarthritis: a randomized controlled trial

Scandinavian Journal of Pain ◽

10.1515/sjpain-2021-0091 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Sophie Vervullens ◽

Lotte Meert ◽

Isabel Baert ◽

Nicolas Delrue ◽

Christiaan H. W. Heusdens ◽

...

Keyword(s):

Knee Osteoarthritis ◽

Controlled Trial ◽

Pain Modulation ◽

Group Differences ◽

Conditioned Pain Modulation ◽

Pain Processing ◽

Central Pain ◽

Dry Needling ◽

Spatiotemporal Parameters ◽

Central Pain Processing

Abstract Objectives To assess the immediate and three days postintervention effect of one dry needling session compared to one sham needling session on pain, central pain processing, muscle co-contraction and spatiotemporal parameters during gait in knee osteoarthritis patients. Methods A double-blind randomized controlled trial was conducted. Sixty-one knee osteoarthritis patients were randomly assigned to the dry needling or sham needling group. Primary outcomes were pain and central pain processing. Secondary outcomes included muscle co-contraction and spatiotemporal parameters during gait. Patients were assessed at baseline and 15 min after the intervention, and pain also three days after the intervention. Linear mixed models were used to examine between- and within-group differences. Results No significant between-group differences for pain were found, but within-group scores showed a significant decrease 15 min after sham needling and three days after dry needling. The mean conditioned pain modulation effect measured at the m. Trapezius worsened significantly 15 min after sham needling compared to after dry needling (between-group difference). However, individual conditioned pain modulation percentage scores remained stable over time. Various significant within-group differences were found 15 min after sham needling: a decrease of conditioned pain modulation measured at m. Quadriceps and m. Trapezius and stride- and step-time scores, and an increase in step length and widespread pain pressure threshold. A significant decrease in muscle co-contraction index of the m. Vastus Medialis and Semitendinosus was found as within-group difference 15 min after dry needling. Conclusions Dry needling has no larger effect on pain, central pain processing, muscle co-contraction and gait pattern 15 min and three days postintervention compared to sham needling. Mean conditioned pain modulation scores worsened after sham needling compared to after dry needling. Further research remains necessary.

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(294) The association of psychological resilience and conditioned pain modulation is moderated by optimism in adults with symptomatic knee osteoarthritis

Journal of Pain ◽

10.1016/j.jpain.2017.02.187 ◽

2017 ◽

Vol 18 (4) ◽

pp. S49

Author(s):

K. Thompson ◽

H. Bulls ◽

K. Sibille ◽

E. Bartley ◽

L. Bradley ◽

...

Keyword(s):

Knee Osteoarthritis ◽

Pain Modulation ◽

Conditioned Pain Modulation ◽

Psychological Resilience ◽

Symptomatic Knee Osteoarthritis ◽

Symptomatic Knee

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Insight into Pain Modulation: Nociceptors Sensitization and Therapeutic Targets

Current Drug Targets ◽

10.2174/1389450120666190131114244 ◽

2019 ◽

Vol 20 (7) ◽

pp. 775-788 ◽

Cited By ~ 5

Author(s):

Amna Khan ◽

Salman Khan ◽

Yeong Shik Kim

Keyword(s):

Ion Channels ◽

Cannabinoid Receptors ◽

Transient Receptor Potential ◽

Receptor Potential ◽

Experimental Models ◽

Pain Modulation ◽

Metabotropic Glutamate ◽

Pain Sensitization ◽

Neurokinin 1 ◽

Pain Transduction

Pain is a complex multidimensional concept that facilitates the initiation of the signaling cascade in response to any noxious stimuli. Action potential generation in the peripheral nociceptor terminal and its transmission through various types of nociceptors corresponding to mechanical, chemical or thermal stimuli lead to the activation of receptors and further neuronal processing produces the sensation of pain. Numerous types of receptors are activated in pain sensation which vary in their signaling pathway. These signaling pathways can be regarded as a site for modulation of pain by targeting the pain transduction molecules to produce analgesia. On the basis of their anatomic location, transient receptor potential ion channels (TRPV1, TRPV2 and TRPM8), Piezo 2, acid-sensing ion channels (ASICs), purinergic (P2X and P2Y), bradykinin (B1 and B2), α-amino-3-hydroxy-5- methylisoxazole-4-propionate (AMPA), N-methyl-D-aspartate (NMDA), metabotropic glutamate (mGlu), neurokinin 1 (NK1) and calcitonin gene-related peptide (CGRP) receptors are activated during pain sensitization. Various inhibitors of TRPV1, TRPV2, TRPM8, Piezo 2, ASICs, P2X, P2Y, B1, B2, AMPA, NMDA, mGlu, NK1 and CGRP receptors have shown high therapeutic value in experimental models of pain. Similarly, local inhibitory regulation by the activation of opioid, adrenergic, serotonergic and cannabinoid receptors has shown analgesic properties by modulating the central and peripheral perception of painful stimuli. This review mainly focused on various classes of nociceptors involved in pain transduction, transmission and modulation, site of action of the nociceptors in modulating pain transmission pathways and the drugs (both clinical and preclinical data, relevant to targets) alleviating the painful stimuli by exploiting nociceptor-specific channels and receptors.

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Pain perception in chronic knee osteoarthritis with varying levels of pain inhibitory control: an exploratory study

Scandinavian Journal of Pain ◽

10.1515/sjpain-2020-0016 ◽

2020 ◽

Vol 20 (4) ◽

pp. 651-661

Author(s):

Paulo E. P. Teixeira ◽

Hanan I. Zehry ◽

Swapnali Chaudhari ◽

Laura Dipietro ◽

Felipe Fregni

Keyword(s):

Knee Osteoarthritis ◽

Pain Intensity ◽

Pain Perception ◽

Small Sample Size ◽

Linear Regression Analysis ◽

Small Sample ◽

Pain Modulation ◽

Clinical Variables ◽

Pain Scores ◽

Intensity Perception

AbstractBackground and aimsPain is a disabling symptom in knee osteoarthritis (KOA) and its underlying mechanism remains poorly understood. Dysfunction of descending pain modulatory pathways and reduced pain inhibition enhance pain facilitation in many chronic pain syndromes but do not fully explain pain levels in chronic musculoskeletal conditions. The objective of this study is to explore the association of clinical variables with pain intensity perception in KOA individuals with varying levels of Conditioned Pain Modulation (CPM) response.MethodsThis is a cross-sectional, exploratory analysis using baseline data of a randomized clinical trial investigating the effects of a non-invasive brain stimulation treatment on the perception of pain and functional limitations due to KOA. Sixty-three subjects with KOA were included in this study. Data on pain perception, mood perception, self-reported depression, physical function, quality of life, and quantitative sensory testing was collected. Multiple linear regression analysis was performed to explore the association between the clinical variables with pain perception for individuals with different levels of CPM response.ResultsFor KOA patients with limited CPM response, perception of limitations at work/other activities due to emotional problems and stress scores were statistically significantly associated with pain scores, F(2, 37) = 7.02, p < 0.01. R-squared = 0.275. For KOA patients with normal CPM response, general health perception scores were statistically significantly associated with pain scores, F(1, 21) = 5.60, p < 0.05. R-squared = 0.2104. Limitations of this study include methodology details, small sample size and study design characteristics.ConclusionsPain intensity perception is associated differently with clinical variables according to the individual CPM response. Mechanistic models to explain pain perception in these two subgroups of KOA subjects are discussed.

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