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

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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Comparison of statistical methods for analysis of small sample sizes for detecting the differences in efficacy between treatments for knee osteoarthritis

10.21203/rs.2.20859/v1 ◽

2020 ◽

Author(s):

Chia-Lung Shih ◽

Te-Yu Hung

Keyword(s):

Knee Osteoarthritis ◽

Sample Size ◽

Statistical Methods ◽

Statistical Power ◽

Permutation Test ◽

Small Sample Size ◽

Small Sample ◽

T Test ◽

Sample Sizes ◽

Knee Oa

Abstract Background A small sample size (n < 30 for each treatment group) is usually enrolled to investigate the differences in efficacy between treatments for knee osteoarthritis (OA). The objective of this study was to use simulation for comparing the power of four statistical methods for analysis of small sample size for detecting the differences in efficacy between two treatments for knee OA. Methods A total of 10,000 replicates of 5 sample sizes (n=10, 15, 20, 25, and 30 for each group) were generated based on the previous reported measures of treatment efficacy. Four statistical methods were used to compare the differences in efficacy between treatments, including the two-sample t-test (t-test), the Mann-Whitney U-test (M-W test), the Kolmogorov-Smirnov test (K-S test), and the permutation test (perm-test). Results The bias of simulated parameter means showed a decreased trend with sample size but the CV% of simulated parameter means varied with sample sizes for all parameters. For the largest sample size (n=30), the CV% could achieve a small level (<20%) for almost all parameters but the bias could not. Among the non-parametric tests for analysis of small sample size, the perm-test had the highest statistical power, and its false positive rate was not affected by sample size. However, the power of the perm-test could not achieve a high value (80%) even using the largest sample size (n=30). Conclusion The perm-test is suggested for analysis of small sample size to compare the differences in efficacy between two treatments for knee OA.

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Analgesic efficacy of meloxicam with or without a buprenorphine patch in cats after ovariohysterectomy

Veterinární Medicína ◽

10.17221/148/2017-vetmed ◽

2018 ◽

Vol 63 (No. 6) ◽

pp. 279-286

Author(s):

SY Heo ◽

SJ Kim ◽

NS Kim

Keyword(s):

Visual Analogue Scale ◽

Analogue Scale ◽

Small Sample Size ◽

Analgesic Efficacy ◽

Small Sample ◽

Visual Analogue Scale Pain ◽

Pain Scores ◽

Analogue Scale Pain ◽

Group A ◽

Group B

The purpose of this prospective double blind clinical study was to evaluate the analgesic efficacy of meloxicam with/without a buprenorphine patch for pain management after ovariohysterectomy in cats. Cats were randomly divided into two groups: ten cats were treated with meloxicam s.c. after ovariohysterectomy (Group A), and eight cats were treated with s.c. meloxicam and a 20 µg/h buprenorphine transdermal patch (Group B). For patch treatment, the cat’s hair was clipped on the left side in the thoracic area. Pain scores were assessed at 0.5, 1, 2, 4, 6, 8, 24 and 30 h post-ovariohysterectomy extubation. To evaluate postoperative pain, 4A-VET pain scale and visual analogue scale pain scores were used. In addition, blood was collected from all cats to determine the cortisol levels at –2 h and at 0.5, 4, 6 and 24 h after extubation. The 4A-VET scores for Group B were significantly lower at 1, 4, 6, 8, 24 and 30 h than the scores for Group A. The visual analogue scale pain scores for Group B were significantly lower at 4, 6, 24 and 30 h than the scores for Group A. Serum cortisol concentrations were not significantly different between Groups A and B at any of the measured intervals. There was a significant positive correlation between postoperative visual analogue scale and 4A-VET pain scores in both groups. Our results should be subject to careful interpretation as the study was limited by its small sample size and by observer subjectivity.

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Depressive Attribution Style and Stressor Uncontrollability Increase Perceived Pain Intensity after Electrical Skin Stimuli in Healthy Young Men

Pain Research and Management ◽

10.1155/2013/263084 ◽

2013 ◽

Vol 18 (4) ◽

pp. 203-206 ◽

Cited By ~ 2

Author(s):

Matthias J Müller

Keyword(s):

Pain Intensity ◽

Multiple Regression ◽

Pain Perception ◽

Depression Scale ◽

Stress Exposure ◽

Psychological Pain ◽

Attribution Style ◽

Intensity Perception ◽

Perceived Pain ◽

Electrical Skin

BACKGROUND: Depressive and pain symptoms often occur concurrently in patients with psychiatric disorders or somatic diseases, but the contribution of pre-existing dysfunctional cognitive schemata to pain perception remains unclear.OBJECTIVE: To investigate the relationship between depression-related attribution styles and perceived pain intensity (PPI) after controllable versus uncontrollable electrical skin stimulation in healthy male individuals.METHODS: Causal attributions for negative events were measured using the attribution style questionnaire (ASQ) on the dimensions internal versus external (INT), global versus specific (GLO) and stable versus unstable (STA) in 50 men (20 to 31 years of age). Additionally, symptoms of anxiety and depression (measured using the Depression Scale) as well as baseline helplessness were assessed. Participants were randomly assigned to receive self-administered (controllable) or experimenter-administered (uncontrollable) painful skin stimuli. PPI was assessed after stress exposure using a visual analogue scale (0 to 100). Relationships between PPI and depression-related cognitions were calculated using correlation and multiple regression analyses.RESULTS: Correlation analyses revealed a moderate correlation between PPI and ASQ-INT scores (r=0.46). Following uncontrollable stress exposure, significantly higher PPI ratings (P=0.001) and a higher correlation between PPI and ASQ-INT (r=0.70) were observed. Multiple regression analysis showed an independent influence of stressor controllability (ß=0.39; P=0.003) and ASQ-INT (ß=0.36; P=0.006) on PPI.DISCUSSION: These findings highlight the interaction of specific depression-related cognitions and stress controllability on pain intensity perception.CONCLUSIONS: The results of the present study may facilitate understanding of the cognitive aspects of pain intensity perception and improve psychological pain therapies focusing on attributions and controllability.

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What determines forward-looking information disclosure in Bangladesh?

Asian Journal of Accounting Research ◽

10.1108/ajar-03-2020-0014 ◽

2020 ◽

Vol 5 (2) ◽

pp. 225-239

Author(s):

Pappu Kumar Dey ◽

Manas Roy ◽

Mohsina Akter

Keyword(s):

Information Disclosure ◽

Positive Impact ◽

Small Sample Size ◽

Linear Regression Analysis ◽

Multiple Linear Regression Analysis ◽

Small Sample ◽

Annual Reports ◽

Female Representation ◽

Content Type ◽

Forward Looking

PurposeThe study aims to examine the level and extent of forward-looking information (FLI) disclosure and identify the determinants driving the FLI disclosure (FLID) in the context of an emerging and developing economy.Design/methodology/approachThe sample includes annual reports of the top 30 listed companies in Bangladesh for the years 2013–2017. The content analysis approach is used to examine the practice of FLID and to determine the extent of FLID based on the index. Multiple linear regression analysis is performed to identify the determinants of FLID.FindingsThis research finds that board size, auditor's global affiliation, leverage and profitability have a substantial positive impact on FLID. By contrast, firm size and listing age have a significant negative association with FLID. Moreover, contrary to our expectation, female representation in the boardroom has an inverse effect on FLID. This study, however, does not suggest any significant impact of board independence.Research limitations/implicationsSmall sample size may limit the generalizability of the findings. Besides, the FLID index score may be affected by the subjective judgment while analyzing the content of the annual report.Practical implicationsThe findings of this paper may assist the regulators and policymakers in incorporating this new reporting paradigm in regulations. Alternatively, the current research can serve as a basis to further understand the importance of FLID for the stakeholders.Originality/valueThis empirical study contributes to the current FLI literature in Bangladesh. A handful of studies have been done to examine the nature and level of FLID and find out the determinants of FLID in the developing countries. To the best of the authors' knowledge, no study yet has been explored on FLID and its determinants by classifying them as qualitative and quantitative in Bangladesh.

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Dietary inflammatory index is associated with pain intensity and some components of quality of life in patients with knee osteoarthritis

BMC Research Notes ◽

10.1186/s13104-020-05277-x ◽

2020 ◽

Vol 13 (1) ◽

Author(s):

Vahideh Toopchizadeh ◽

Neda Dolatkhah ◽

Dawood Aghamohammadi ◽

Mahrokh Rasouli ◽

Maryam Hashemian

Keyword(s):

Quality Of Life ◽

Knee Osteoarthritis ◽

Pain Intensity ◽

Functional Status ◽

Linear Regression Analysis ◽

Dietary Inflammatory Index ◽

Emotional Wellbeing ◽

Inflammatory Index ◽

Womac Questionnaire

Abstract Objectives We aim to measure dietary inflammatory index (DII) and its association with functional status, pain intensity and quality of life (QOL) in patients with knee osteoarthritis (KOA). Dietary information from 220 qualified patients with KOA was collected by a 168-item food frequency questionnaire. The functional status, pain intensity and QOL were evaluated by Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire, Visual Analogue Scale (VAS) and SF36 questionnaire respectively. Results Linear regression analysis showed that the DII was significantly associated with VAS (p = 0.040; β = 0.151), and physical function (p = 0.039; β = − 0.184), emotional wellbeing (p = 0.048; β = − 0.158) and pain (p = 0.020; β = 0.161) scales and physical health (p = 0.047; β = 0.110) subscale of QOL after adjusting for age, sex, body mass index, and physical activity. There was no significant differences concerning WOMAC across the DII tertiles with and without adjustment to probable confounders (Ptrend = 0.091 and 0.181, respectively). After adjustment, a significantly increased severe pain odds was observed in the highest tertile of DII score in comparison with the lowest tertile (OR tertile 3 vs. 1 = 1.55, 95% CI 1.04–2.31; Ptrend = 0.04).

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Effect of expectation on pain assessment of lower- and higher-intensity stimuli

Scandinavian Journal of Pain ◽

10.1016/j.sjpain.2016.09.013 ◽

2017 ◽

Vol 14 (1) ◽

pp. 9-14 ◽

Cited By ~ 4

Author(s):

Valentina Ružić ◽

Dragutin Ivanec ◽

Koraljka Modić Stanke

Keyword(s):

Pain Intensity ◽

Pain Perception ◽

Pain Modulation ◽

The Other ◽

Moderate Intensity ◽

Lower Intensity ◽

Intensity Assessment ◽

Potential Benefits ◽

Electrical Stimuli ◽

Experimentally Induced

AbstractBackground and aimsPain modulation via expectation is a well-documented phenomenon. So far it has been shown that expectations about effectiveness of a certain treatment enhance the effectiveness of different analgesics and of drug-free pain treatments. Also, studies demonstrate that people assess same-intensity stimuli differently, depending on the experimentally induced expectations regarding the characteristics of the stimuli. Prolonged effect of expectation on pain perception and possible symmetry in conditions of lower- and higher-intensity stimuli is yet to be studied. Aim of this study is to determine the effect of expectation on the perception of pain experimentally induced by the series of higher- and lower-intensity stimuli.Methods192 healthy participants were assigned to four experimental groups differing by expectations regarding the intensity of painful stimuli series. Expectations of two groups were congruent with actual stimuli; one group expected and received lower-intensity stimuli and the other expected and received higher-intensity stimuli. Expectations of the remaining two groups were not congruent with actual stimuli; one group expected higher-intensity stimuli, but actually received lower-intensity stimuli while the other group expected lower-intensity stimuli, but in fact received higher-intensity ones. Each group received a series of 24 varied-intensity electrical stimuli rated by the participants on a 30° intensity scale.ResultsExpectation manipulation had statistically significant effect on pain intensity assessment. When expecting lower-intensity stimuli, the participants underestimated pain intensity and when expecting higher-intensity stimuli, they overestimated pain intensity. The effect size of expectations upon pain intensity assessment was equal for both lower- and higher-intensity stimuli.ConclusionThe obtained results imply that expectation manipulation can achieve the desired effect of decreasing or increasing both slight and more severe pain for a longer period of time. Manipulation via expectation before the stimuli series was proven to be effective for pain modulation in the entire series of stimuli which lasted around 10 min. The results suggest a potential benefit of manipulating expectations to alleviate emerging pain, since the obtained effects are moderate to large.ImplicationsIt seems that expectation effect is strong enough to “overcome” even the direct effect of stimulus intensity (at least in the low to moderate intensity range), which suggests potential benefits of verbal instructions even in rather painful stimuli.

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Interferential current and photobiomodulation in knee osteoarthritis: A randomized, placebo-controlled, double-blind clinical trial

Clinical Rehabilitation ◽

10.1177/02692155211012004 ◽

2021 ◽

pp. 026921552110120

Author(s):

Renata Alqualo-Costa ◽

Érika Patrícia Rampazo ◽

Gustavo Ribeiro Thome ◽

Mônica Rodrigues Perracini ◽

Richard Eloin Liebano

Keyword(s):

Clinical Trial ◽

Knee Osteoarthritis ◽

Pain Intensity ◽

Rating Scale ◽

Pain Modulation ◽

Double Blind ◽

Time Points ◽

Double Blind Clinical Trial ◽

Interferential Current

Objectives: To evaluate the effects of interferential current and photobiomodulation in patients with knee osteoarthritis. Design: A randomized, placebo-controlled, double-blind clinical trial. Setting: Physiotherapy Clinic of City University of São Paulo. Subjects: A total of 184 patients with knee osteoarthritis were recruited and, of these, 168 were included and randomized into four groups with 42 each: interferential current, photobiomodulation, interferential current plus photobiomodulation or placebo groups. One hundred and sixty-four patients completed the study. Intervention: Patients received 12 sessions (three times a week) of treatment: 30 minutes of interferential current (active or placebo) followed by photobiomodulation (active or placebo). Main measures: Primary outcome: pain intensity at rest and during movement (numeric rating scale) after 12 sessions. Secondary outcomes: functional capacity (Timed Up & Go and Sit and Lift tests and Lequesne and WOMAC questionnaires), pressure pain threshold, conditioned pain modulation, and muscle strength production (isokinetic evaluation). Patients were assessed at baseline, after 12 sessions, and three and six months after the end of the treatment. Results: Interferential current plus photobiomodulation reduced pain intensity at rest and during movement compared to placebo and interferential current at all time points ( P < 0.05). Photobiomodulation reduced pain intensity at rest compared to placebo at all time points ( P < 0.05) and compared to interferential current at six months follow-up ( P < 0.05). Photobiomodulation reduced pain intensity during movement compared to placebo at six months follow-up ( P < 0.05). Conclusion: Interferential current plus photobiomodulation or isolated photobiomodulation improve pain intensity in knee osteoarthritis.

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The Effects of Gastroretentive Gabapentin (Gralise®) on Spinal Stenosis Patients with Radicular Pain

January 2018 - Pain Physician ◽

10.36076/ppj.2014/17/169 ◽

2014 ◽

Vol 2;17 (2;3) ◽

pp. 169-178

Author(s):

Alan David Kaye

Keyword(s):

Pain Intensity ◽

Spinal Stenosis ◽

Small Sample Size ◽

Medical Center ◽

Radicular Pain ◽

Small Sample ◽

Open Label ◽

Sleep Diaries ◽

Significant Positive Change ◽

Global Impression Of Change

Background: The health and efficacy profiles of Gralise® in the treatment of pain from spinal stenosis and radicular symptomatology have not been measured. A review of the current literature indicates that no studies exist that evaluate the safety and efficacy profiles of Gralise® in the treatment of pain from spinal stenosis and radicular symptomatology. Objective: Our study is aimed at determining whether Gralise is a safe and effective pharmacotherapy for the pain from spinal stenosis and radicular symptomatology. Study Design: A 4-week prospective open label single arm and single center study of patients with MRI diagnosis of spinal stenosis with radicular pain. Methods: The primary measure of efficacy was a change in average daily pain (ADP) score from baseline to completion of Gralise therapy for 4 weeks. The secondary efficacy endpoints were the patients’ Patients Global Impression of Change Scale (PGIC), the clinician’s Clinical Global Impression of Change Scale (CGI) reports, and the Medical Outcomes Study (MOS) sleep scale of improvement from baseline to completing 4 weeks of Gralise therapy. The safety and tolerability were evaluated by the incidence of adverse events reported while on Gralise therapy. Setting: The study was performed at the Clinical Research Facilities at Tulane Medical Center, New Orleans, Louisiana, in the period from December 1, 2012, to August 30, 2013. Results: Thirty-five patients achieved an efficacy point of one-week Gralise medication treatment. Twenty-seven of 35 (77.2%) patients completed all 5 visits. The PGIC noted a significant positive change in: (1) activity limitations; (2) symptoms; (3) emotions and overall quality of life when related to their condition from first visit as well as improved degree of change when related to their condition from first to last visit. The MOS sleep scale and sleep diaries noted a significant increase of hours slept on average (an increase in over one hour per night — 5.8 hours versus 6.86 hours) from the beginning of the study to the end. The CGI noted a majority of 10 out of 27 with marked significant therapeutic effect with no side effects. The ADP rating from pain intensity scale and pain diaries noted significant improvement of lesser levels of pain experienced (P =.5907 and P =.8547 respectively). No significant adverse effects were noted in the study. Limitations: Variation in degree of spinal stenosis, small sample size. Conclusions: Gralise demonstrated moderate efficacy with reduced pain intensity and increased sleep and was well tolerated in spinal stenosis patients with radicular symptoms. Key words: Spinal stenosis, gabapentin, Gralise®, radicular pain, neuropathic pain

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Using intra-articular allogenic lyophilized growth factors in primary knee osteoarthritis: a randomized pilot study

Regenerative Medicine ◽

10.2217/rme-2020-0104 ◽

2021 ◽

Vol 16 (2) ◽

pp. 113-115

Author(s):

Rasmia El-Gohary ◽

Amany Diab ◽

Hala El-Gendy ◽

Hossam Fahmy ◽

Kamel Heshmat Gado

Keyword(s):

Growth Factors ◽

Pilot Study ◽

Knee Osteoarthritis ◽

Small Sample Size ◽

Intervention Group ◽

Small Sample ◽

Injection Pain ◽

Post Injection ◽

Open Label ◽

Clinical Trial Registration

Objective: Investigating the safety in addition to clinical and structural efficacy of allogenic lyophilized growth factors (L-GFs) in patients with symptomatic primary knee osteoarthritis. Design: A prospective, open-label pilot study. A total of 31-patients randomized into non-intervention and intervention groups. Materials & methods: The intervention group received two intra-articular doses at baseline and after 2-months. Post-injection complications were documented, and the efficacy was assessed by Western Ontario and McMaster Universities Osteoarthritis Index scores and ultrasonography. Results: One dropout from the intervention group. The percentage of improvement of mean Western Ontario and McMaster Universities Osteoarthritis Index-scores and ultrasonography-detected effusion were statistically significant in the intervention group compared with the non-intervention. A brief, mild, post-injection pain was reported by all intervention group. Conclusion: This study provides the safety of intra-articular injection of allogenic L-GFs in knee osteoarthritis. The conclusion of efficacy was limited by small sample size and lack of control injection. Clinical trial registration: NCT04331327 (ClinicalTrials.gov, retrospectively registered).

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