Volume 20, Issue 4

Background and aims Pain 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. Methods This 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. Results For 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. Conclusions Pain 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.

Background and aims The ACR1990 criteria of fibromyalgia (FM) have been criticized due to poor reliability of tender points counting (TPC), inconsistent definitions of the widespread pain, and by not considering other symptoms than pain in the FM phenotype. Therefore, several newer self-report measures for FM criteria have emerged. The aim of this study was to translate the fibromyalgia survey questionnaire (FSQ) to Norwegian and validate both the 2011 and the 2016 fibromyalgia survey diagnostic criteria (FSDC) against the ACR1990 criteria. Methods One hundred and twenty chronic pain patients formerly diagnosed with fibromyalgia according to the ACR1990 criteria, and 62 controls not diagnosed or where fibromyalgia was not suspected, were enrolled in this study. All responded to a Norwegian version of the FSQ. Also, they had a clinical examination according to ACR1990 fibromyalgia criteria including a counting of significant tender points with an algometer (TPC). The FSQ with the Widespread Pain Index (WPI) and Symptom Severity scale (SSS) subscales, Fibromyalgia Severity (FS) sum score, was examined for correlations with the fibromyalgia impact questionnaire (FIQ) and TPCs. Face-validity, internal consistence, test-retest reliability and construct validity with convergent and divergent approaches were examined and a Receiver Operating Characteristics (ROC) analysis was performed. Results The internal consistency of FS measured by Cronbach’s alfa was good (=0.904). The test-retest reliability measures using intra class correlation were respectable for the FS, including WPI and SSS subscales (0.86, 0.84 and 0.87). FS, WPI and SSS correlated significantly with FIQ (0.74, 0.59 and 0.85) and TPC indicating an adequate construct, convergent validity. The medians of FS, WPI and SSS in the fibromyalgia-group were significantly different from the non-fibromyalgia-group indicating good construct, divergent validity. Using the 2011 and 2016 FSDC vs. ACR 1990 as a reference, sensitivity, specificity, positive likelihood ratio (LR +) and negative likelihood ratio (LR−) were identified. The accuracy rate for both 2011 and 2016 FSDC were respectable (84%). ROC analysis using FS revealed a very good Area Under the Curve (AUC) = 0.860. Conclusion The current study revealed that the Norwegian versions of FSQ is a valid tool for assessment of fibromyalgia according to the 2011 and 2016 (FSDC).

Background and Aims Higher chronic pain acceptance is associated with lower pain and disability. Clinician beliefs are associated with patients’ beliefs. This study therefore aimed to develop the Chronic Pain Acceptance Questionnaire for Clinicians (CPAQ-C) to measure clinicians’ beliefs regarding the importance of levels of acceptance in patients with chronic pain, and to examine the questionnaire’s psychometric properties. Methods Phase one : the CPAQ-C was adapted from the Chronic Pain Acceptance Questionnaire. Data on 162 completed questionnaires were analysed using Rasch analysis. Phase Two : the cohort completed the Healthcare Providers Pain and Impairment Relationship Scale, and the association (Pearson’s correlation co-efficient) between these questionnaires examined to assist CPAQ-C validation. Twenty-four participants completed the CPAQ-C one-week later. Test re-test reliability was examined using intraclass correlation co-efficient (2,1) and standard error of measurement. Phase Three : to examine responsiveness 17 clinicians attending a workshop on Acceptance and Commitment Therapy completed the CPAQ-C before and immediately after the workshop, and six-months later. The Skillings Mack test was used to determine whether CPAQ-C scores differed across different timepoints. Results Rasch analysis supported two subscales: activity engagement and pain willingness. Five poorly functioning items were excluded. There was good correlation between the CPAQ-C and Healthcare Providers Pain and Impairment Relationship Scale (-.54). The CPAQ-C demonstrated good reliability (ICC (2,1): .81; standard error of measurement: 4.76). There was significant improvement in CPAQ-C scores following the workshop ( p =<.001). Conclusions The CPAQ-C appears a valid, reliable and responsive measure of clinicians’ beliefs regarding the importance of levels of acceptance in patients with chronic pain. Implications Where the CPAQ-C reveals that clinicians have low perceived levels of importance regarding acceptance in patients with chronic pain those clinicians may benefit from specific education, however, this requires further examination.

Objectives Static mechanical allodynia (SMA), i. e., pain caused by normally non-painful static pressure, is a prevalent manifestation of neuropathic pain (NP). Although SMA may significantly affect the patient’s daily life, it is less well studied in the clinical context. We aimed to characterize SMA in women with chronic post-surgical NP (CPSNP) after breast cancer surgery. Our objective was to improve understanding of the clinical picture of this prevalent pain condition. This is a substudy of a previously published larger cohort of patients with intercostobrachial nerve injury after breast cancer surgery (Mustonen et al. Pain. 2019;160:246–56). Methods We studied SMA in 132 patients with CPSNP after breast cancer surgery. The presence, location, and intensity of SMA were assessed at clinical sensory examination. The patients gave self-reports of pain with the Brief Pain Inventory (BPI). We studied the association of SMA to type of surgery, oncological treatments, BMI, other pains, and psychological factors. General pain sensitivity was assessed by the cold pressor test. Results SMA was prevalent (84%) in this cohort whereas other forms of allodynia were scarce (6%). Moderate-to-severe SMA was frequently observed even in patients who reported mild pain in BPI. Breast and the side of chest were the most common locations of SMA. SMA was associated with breast surgery type, but not with psychological factors. Severe SMA, but not self-reported pain, was associated with lower cold pain tolerance. Conclusions SMA is prevalent in post-surgical NP after breast cancer surgery and it may represent a distinct NP phenotype. High intensities of SMA may signal the presence of central sensitization. Implications SMA should be considered when examining and treating patients with post-surgical NP after breast cancer surgery.

Objectives Chronic postoperative pain is prevalent after robot-assisted laparoscopic hysterectomy for endometrial cancer. Preoperative Quantitative Sensory Testing (QST) has been utilized to identify patients at risk of developing chronic postoperative pain after a range of surgical procedures. The aim of this prospective, observational study was to (1) determine the prevalence of chronic postoperative pain, (2) assess selected preoperative risk factors for chronic postoperative pain, and (3) evaluate if preoperative QST profiling could predict the development of chronic postoperative pain following robot-assisted laparoscopic hysterectomy for endometrial cancer. Methods One-hundred and sixty consecutive patients were included and handheld pressure algometry, cuff pressure algometry, temporal summation of pain, conditioned pain modulation, and heat pain thresholds were assessed prior to surgery. Patients were asked to fill out a questionnaire concerning pain in the pre- and post-operative time period six months after surgery. Chronic postoperative pain was defined as persistent, moderate to severe pain (mean visual analogue scale (VAS)≥3) on a daily basis six months after surgery. Results The prevalence of chronic postoperative pain after robot-assisted laparoscopic hysterectomy for endometrial cancer was of 13.6% (95% CI 8.4–20.4%). Patients that would develop chronic postoperative pain had a lower BMI (p=0.032), a higher prevalence of preoperative pelvic pain (p<0.001), preoperative heat pain hyperalgesia (p=0.043) and a higher level of acute postoperative pain (p<0.001) when compared to patients that would not develop chronic postoperative pain. A logistic regression model demonstrated that the presence of preoperative pelvic pain was a significant, independent predictive risk factor for development of chronic postoperative pain (OR=6.62, 95% CI 2.26–19.44), whereas none of the QST parameters could predict postoperative pain. Conclusions Preoperative QST assessment could not predict the development of chronic postoperative pain despite preoperative heat pain hyperalgesia in patients that would develop chronic postoperative pain.

Objectives Complex regional pain syndrome (CRPS) is a rare chronic pain condition for which no curative treatment exists. Patients in tertiary centres are often required to make decisions about treatment options. This study was conducted to explore how prior attendance of a pain management program might alter patients’ decision making processes. Methods This qualitative study uses focus groups to gather patient views on an immunosuppressant drug treatment (mycophenolate) for the management of CRPS. Participants were allocated to one of three focus groups based on their treatment journey; Group 1 (n=3) were involved in a recent mycophenolate drug trial; Group 2 (n=5) were neither involved in the trial nor attended a Pain Management Programme (PMP); Group 3 (n=6) were not involved in the trial but had attended a PMP. Outcomes were considered within the framework of Leventhal’s Common Sense Model (CSM) in relation to the decision making process. Results Thematic analysis identified differing themes for each group. Group 1: (1) Medication as a positive form of treatment, (2) The trial/drug and (3) Pacing. Group 2: (1) Medication as form of treatment, (2) Other forms of support/treatment and (3) Side effects of mycophenolate. Group 3: (1) Varied view of medication, (2) Consideration of other forms of support and (3) Side effects. Conclusions Attendance on a PMP might provide patients with skills to better manage uncertainty when faced with various treatment options. Leventhal’s model goes some way to explaining this. The specific importance of, and benefit from understanding pacing when commencing an effective drug treatment for chronic pain became apparent.

Objectives Depression symptomatology is highly prevalent in patients with chronic pain, but accurate identification of major depression may be challenged due to time constraints and diagnostic interviews are therefore not routinely performed in clinical practice. Assessment of depression may be facilitated through the use of full-length depression screening questionnaires with acceptable construct validity and test-retest reliability. However, as previously indicated screening questionnaires may overestimate depression in patients with chronic pain, possibly due to overlapping symptoms. However, the failure to screen for depression may raise a concern for missing relevant cases with depression. The objectives of this study were to (1) quantify the validity of the 9-items Patient-Health Questionnaire (PHQ9) and the Major Depression Inventory (MDI) compared with a diagnostic interview in patients with chronic pain seeking specialist pain treatment, and (2) assess the relative test-retest reliability of PHQ9 and MDI over two weeks. Methods Responses to the PHQ9 and MDI were compared with a Present-State-Examination (PSE) interview in 99 patients with chronic pain referred to interdisciplinary pain treatment. PHQ9 and MDI were completed twice over two weeks. Construct validity were assessed with the area under the curve (AUC) analysis, and performance characteristics derived from 2 × 2 contingency tables in which scores on the screening questionnaires were dichotomized and compared with the classification of clinical depression based on the diagnostic interview. Relative test-retest reliability was assessed with intraclass correlation coefficients (ICC). Results Based on the PSE interview, the prevalence of depression was 22.2%, and according to the PHQ9 and MDI questionnaires the prevalence was 26.3 and 34.3%, respectively. Compared with the diagnostic PSE, the PHQ9 and MDI questionnaires had areas under the curve of 0.83 and 0.88, respectively. Both questionnaires had high negative predictive values (PHQ9: cut-off of 11; MDI: cut-off of 26), but low positive predictive values for all possible scores. ICC values were excellent. Conclusions The PHQ9 and MDI questionnaires reliably identified chronic pain patients unlikely to have clinical depression, but showed limited validity identifying patients with clinical depression. These preliminary results may have clinical implications in depression screening in patients with chronic pain seeking specialist pain treatment. Clinicians in a specialty care pain clinic can use these screening questionnaires to identify patients without depression, but caution should be used when positive cases are identified by PHQ9 or MDI due to the risk of false positives.

Objectives Fibromyalgia is a chronic widespread pain (CWP) syndrome of unknown etiology with substantial burden of illness and functional impairment. Pain acceptance has emerged as an interesting target of therapy in chronic pain populations, but few studies have yet been done on the effect of pain acceptance on patients with fibromyalgia. The aim of the present study was to examine the relationship between pain acceptance and its impact on function and symptoms in fibromyalgia with both a cross-sectional and longitudinal design. Methods Three hundred and sixty five participants aged 22–70 with fibromyalgia were recruited from the Norwegian Fibromyalgia Association (NFA). They filled out a questionnaire containing the Fibromyalgia Impact Questionnaire (FIQ), measurement of function and symptoms, and Chronic Pain Acceptance Questionnaire (CPAQ), measurement of pain acceptance, in addition to sociodemographic and clinical variables such as degree of fibromyalgia, depression and pain duration (T1 measures). One year after, 87 of the participants filled out the FIQ and clinical measures once again (T2 measures). Unadjusted and adjusted linear regression analyses were performed both for cross-sectional measures at T1 and for longitudinal measures from T1 to T2, with FIQ score as the outcome variable and CPAQ score at T1 as one of the main independent variables. Results Higher CPAQ score was significantly associated with a lower FIQ score at T1, also when adjusting for age, education, work, depression and Fibromyalgianess Score (p<0.01). Lower FIQ score indicate less impact of fibromyalgia on functioning. In addition, two adjusted linear regression models found higher pain acceptance (CPAQ score) at T1 to be associated with lower negative impact of fibromyalgia on function and symptoms (FIQ score) at T2 (p<0.01). Conclusions Higher pain acceptance is associated with better functional level and less symptoms in fibromyalgia, both cross-sectionally and when measurements are separated in time. Further research should include experimental studies with acceptance-based interventions for this patient group.

Objectives Cooled radiofrequency (cRF) is an effective treatment for sacroiliac pain. In contrast to conventional radiofrequency denervation, this technique allows enlarging the area of denervation by cooling the radiofrequency probe. However, there is sparse knowledge about the impact of interventional procedures like cRF treatment of sacroiliac joint pain on psychological comorbidities. The aim of this retrospective study was to evaluate the outcome of cRF in chronic pain patients regarding the psychological outcomes anxiety, depression, sleep quality and pain related disability. Methods In this retrospective observational study 29 interventions were performed over a period of two years in 28 patients. Pre- and post-interventional pain levels, depression and anxiety scores, pain-related disability, treatment satisfaction and sleep quality were assessed by standardized and validated questionnaires. Pain medication was recorded prior to the intervention and at follow-up. Results Hospital Anxiety and Depression Scale (HADS-D) scores for depression showed a statistically significant reduction after therapy which did not remain significant after Bonferroni-Holm correction. Anxiety as measured by the HADS-A score did not show a statistically significant change. No statistically significant improvement was observed in the pain disability index. Patients reported fewer sleep disorders after treatment. Mean pain (NRS) was statistically significantly reduced 1 week post intervention and at time of follow-up. There was no clear reduction of analgesic medication. Conclusions Besides pain reduction, our data show a positive influence on sleep quality, possibly on depression, but not on anxiety and pain disability.

Objectives A trend for gender-related differences in pain perception during colonoscopies has previously been observed. No consecutive clinical studies have been conducted to confirm such a relation. We aimed to investigate gender-related differences during the colonoscopy procedure, and the impact of endoscopic equipment and psychological factors on pain management. Methods In a consecutive clinical study, 391 patients referred for colonoscopy reported pain perception on a 0–10 visual analogue scale (VAS) after the procedure. A sub-group of patients (n=38) were given alternate instructions expertly tailored by a psychologist and their VAS scores were compared with those from the main study population. Data from a previous study from the same specialist practice and same source patient population using previous-generation equipment was included for comparison. Results No overall gender-related difference in VAS reports was found. There was no reduction in VAS when alternate instructions were given. Female patients were, however, more likely to benefit from light sedation (p=0.012). When compared with previous-generation endoscopes, the current generation equipment resulted in a VAS drop of 1.9 points for women and 1.6 for men (p<0.009) and washed out a previously observed gender-related difference. Conclusion No overall gender-related differences were found for pain experience during the colonoscopy procedure. Access to up-to-date endoscopic equipment can reduce procedure-related patient discomfort considerably, even at the expert level of a consultant physician. Implications Gastroenterologists should consider utilizing high-end endoscopic equipment to improve pain management and reduce VAS to very acceptable levels.

Objectives Long-term opioid use after hip fracture surgery has been demonstrated in previously opioid-naïve elderly patients. It is unknown if the opioid type redeemed after hip surgery is associated with long-term opioid use. The aim of this study was to examine the association between the opioid type redeemed within the first three months after hip fracture surgery and opioid use 3–12 months after the surgery. Methods A nationwide population-based cohort study was conducted using data from Danish health registries (2005–2015). Previously opioid-naïve patients registered in the Danish Multidisciplinary Hip Fracture Registry, aged ≥65 years, who redeemed ≥1 opioid prescription within three months after the surgery, were included. Long-term opioid use was defined as ≥1 redeemed prescription within each of three three-month periods within the year after hip fracture surgery. The proportion with long-term opioid use after surgery, conditioned on nine-month survival, was calculated according to opioid types within three months after surgery. Adjusted odds ratios (aOR) for different opioid types were computed by logistic regression analyses with 95% confidence intervals (CI) using morphine as reference. Subgroup analyses were performed according to age, comorbidity and calendar time before and after 2010. Results The study included 26,790 elderly, opioid-naïve patients with opioid use within three months after hip fracture surgery. Of these patients, 21% died within nine months after the surgery. Among the 21,255 patients alive nine months after surgery, 15% became long-term opioid users. Certain opioid types used within the first three months after surgery were associated with long-term opioid use compared to morphine (9%), including oxycodone (14%, aOR; 1.76, 95% CI 1.52–2.03), fentanyl (29%, aOR; 4.37, 95% CI 3.12–6.12), codeine (13%, aOR; 1.55, 95% CI 1.14–2.09), tramadol (13%, aOR; 1.56, 95% CI 1.35–1.80), buprenorphine (33%, aOR; 5.37, 95% CI 4.14–6.94), and >1 opioid type (27%, aOR; 3.83, 95% CI 3.31–4.44). The proportion of long-term opioid users decreased from 18% before 2010 to 13% after 2010. Conclusions The findings suggest that use of certain opioid types after hip fracture surgery is more associated with long-term opioid use than morphine and the proportion initiating long-term opioid use decreased after 2010. The findings suggest that some elderly, opioid-naïve patients appear to be presented with untreated pain conditions when seen in the hospital for a hip fracture surgery. Decisions regarding the opioid type prescribed after hospitalization for hip fracture surgery may be linked to different indication for pain treatment, emphasizing the likelihood of careful and conscientious opioid prescribing behavior.

Objectives Acute Epstein-Barr virus (EBV) infection is a trigger of Chronic Fatigue (CF) and Chronic Fatigue Syndrome (CFS). The aim of this cross-sectional study was to investigate pain symptoms and pressure pain thresholds in fatigued and non-fatigued adolescents six months after acute EBV-infection, and in healthy controls. This study is part of the CEBA-project (CF following acute EBV infection in adolescents). Methods A total of 195 adolescents (12–20 years old) that had undergone an acute EBV infection six months prior to assessment were divided into fatigued (EBV CF+) and non-fatigued (EBV CF−) cases based on questionnaire score. The EBV CF+ cases were further sub-divided according to case definitions of CFS. In addition, a group of seventy healthy controls was included. Symptoms were mapped with questionnaires. Pressure pain thresholds were measured through pressure algometry. One way ANOVA were used for between-group analyses. Linear regression analyses were used to explore associations between Pediatric Quality of Life (dependent variable), pain symptoms and other variables within the EBV (CF+) group. Results The EBV CF+ group had significantly higher scores for pain symptoms as compared with the EBV CF− group and healthy controls, but pressure pain threshold did not differ significantly. The number of pain symptoms as well as pain severity were strongly and independently associated with quality of life. Conclusions CF and CFS following acute EBV-infection in adolescents is characterized by high pain symptom burden, which in turn is associated with a decline in quality of life. Pain in CF and CFS is of considerable clinical importance, and should be a focal point for further investigation and intervention in these patient groups.

Objectives Recommendations for referral of patients with shoulder pain from primary to specialist care are mainly clinical. Several patients are referred without meeting these criteria for referral, whereas some are referred for a second opinion although surgery is not recommended. The aims of this study were to describe a shoulder pain cohort in specialist healthcare according to demographic data, clinical, and psychological factors; evaluate changes in pain and disability, distress and main symptoms from baseline to six-month follow-up; and to assess predictors of pain and disability, changes in the main symptoms and sick-leave at six-months. Results were compared to previous randomised trials conducted at the same clinic in patients with subacromial shoulder pain. Methods This prospective study included 167 patients from an outpatient clinic in specialist healthcare with shoulder pain for more than 6 weeks. Clinical (pain duration, intensity, pain sites), sociodemographic (age, gender, educational level, work status) and psychological variables (emotional distress (HSCL-10), fear of pain, screening of “yellow flags”, health-related quality of life) were collected. Shoulder pain and disability (SPADI-score) were assessed and the patients were asked about their outcome expectation and to predict their status of their shoulder problem the next month. They underwent a clinical interview, a clinical assessment of shoulder function and orthopaedic tests for diagnostic purposes. After six months they received a questionnaire with main variables. Results Of the 167 patients (55% women), 50% had symptoms for more than 12 months and 37 (22%) were on sick-leave. Characteristics were in general comparable to patients previously included in clinical trials at the same department. The SPADI-score was 46 (23) points. Mean emotional distress was within the normal range (1.7 (SD 0.6)). More than 80% had received treatment before, mainly physiotherapy in addition to the GPs treatment. One hundred and thirty-seven patients (82%) were re-referred to physiotherapy, 74 (44%) in the outpatient clinic specialist healthcare, and 63 (38%) in primary care. One hundred and eighteen (71%) answered the follow-up questionnaire. Mean change in SPADI-score was 10.5 points (95% CI (6.5–14.5)), and 29% of the patients improved more than the smallest detectable difference (SDD). The percentage sick-listed was 19.5%, and mean change in main symptoms (−9 to +9) was 3.4 (SD 3.9). The subgroup of patients receiving physiotherapy in outpatient specialist care did not show any significant change in the main variables. The prediction models suggested that a lower level of education, more fear of pain and a high baseline SPADI-score, predicted a higher SPADI-score at follow-up. A high baseline HSCL-10 score was the only significant predictor for a high HSCL-10 score. At follow-up, less pain at rest predicted more change in main symptoms and more yellow flags (a higher score on the Örebro screening test) predicted sick-leave. Conclusions Within the limitations of a cohort study, patients with persistent shoulder pain referred to an outpatient specialist clinic had similar baseline characteristics but shorter treatment duration, inferior clinical results and predictors somewhat different compared with previous clinical trials conducted at the same clinic. The study raises some questions about the effectiveness of the routines in daily clinical practice, the selection of patients, the treatment duration and content.

Background and aims The pathophysiology of spinal cord injury is very complex. One of the debilitating aspects of spinal cord injury in addition to pain is a defect in motor function below the lesion surface. In this study, we tried to assess the modulatory effect of (S)-3,4-Dicarboxyphenylglycine (DCPG), a metabotropic glutamate receptor subtype 8 (mGluR8) agonist, on animal’s locomotor functions in a model of compression spinal cord injury. Methods We used a contusion method (T6-T8) for induction of spinal cord injury. Male Wistar rats were randomly assigned to five equal groups ( n  = 10 per group). Clips compression injury model was used to induce spinal cord injury. Three weeks post injury DCPG, siRNA (small interfering Ribonucleic Acid) and normal saline (vehicle) were administered intra-ventrolaterally to the periaqueductal gray (PAG) region. Motor function, were assessed through BBB (Basso, Beattie, and Bresnahan Locomotor Rating Scale) and ladder walking test. In addition, the effects of DCPG on axonal regeneration in corticospinal tract were evaluated. Results We found that DCPG could improve motor function and axonal regeneration in corticospinal tract when compared to siRNA group. Conclusions The results revealed that activation of mGluR8 in PAG is capable to improve motor function and of axonal regeneration due to the inhibitory effect on glutamate transmission on the spinal cord surface and also the elimination of the deleterious effect of glutamate on the regeneration of the injured area as an excitatory neurotransmitter. Implications Our findings in this study showed that, more attention should be paid to glutamate and its receptors in spinal cord injury studies, whether at the spinal or cerebral level, especially in the field of motor function after spinal cord injury.

Background and aims Women with chronic pelvic pain represent a heterogeneous group, and it is suggested that the existence of sub-groups can explain varying results and inconclusiveness in clinical trials. Some predictors of treatment outcome are suggested, but the evidence is limited. The primary aim of this study was to explore if selected pre-treatment characteristics of the participants in a recently conducted randomized controlled trial were associated with treatment outcome. Methods In this study secondary analysis of data collected in a randomized trial were conducted. The participants were women with chronic pelvic pain randomized to two different physical therapy treatments. Analyses in this study were performed for the whole group as a cohort. The primary outcome measure was change in pain intensity from baseline to 12 months, measured with the numeric rating scale (0–10). The women were asked to rate their mean pelvic pain intensity during the last 7 days. Based on previous research and on available variables from the randomized controlled trial four potential predictive factors were derived from the baseline data and assessed one by one in a linear regression model, adjusted for age and treatment group. The variables with strongest association ( p  < 0.10) with the primary outcome were further included in a multivariable linear regression model with backward selection, adjusted for age and treatment group. Results Fifty women (mean age 38.1, SD = 12.2) were included in the analysis. For these women the mean change in pain intensity was −1.2 points (95% CI −1.8 to −0.7) from baseline to 12 months. The multivariable regression model showed that pelvic pain duration of 6 years or more was associated with less decrease in pain intensity with a regression coefficient of 1.3 (95% CI 0.3–2.4). Baseline pain intensity was associated with higher pain reduction after PT treatment with a regression coefficient per SD increase in baseline pain of −0.6 (95% CI −1.1 to −0.1). None of the women with main pain site other places than in the pelvis reported any pain reduction after physical therapy treatment, but due to the small numbers the predictor was not included in the regression analysis. Conclusions We identified that pelvic pain duration of 6 years or more was associated with less pain reduction, and that higher baseline pain intensity was associated with higher pain reduction after physical therapy treatment in this sample of women with chronic pelvic pain. For the variable main pain site other places than the pelvis the results are unsure due to small numbers. Implications Based on our finding of long pain duration as a negative predictor for pain reduction, we emphasize that early intervention is important. Many of the participants in our RCT reported pelvic surgeries or other treatments prior to referral for PT, and we suggest that referral to a non-invasive intervention such as PT should be considered at an earlier stage. In order to tailor interventions to the individual women’s needs, thorough baseline assessments, preferably in a multidisciplinary setting, should be performed.

Background and aims In recent years, focus on assessing descending pain modulation or conditioning pain modulation (CPM) has emerged in patients with chronic pain. This requires reliable and simple to use bed-side tools to be applied in the clinic. The aim of the present pilot study was to develop and provide proof-of-concept of a simple clinically applicable bed-side tool for assessing CPM. Methods A group of 26 healthy volunteers participated in the experiment. Pressure pain thresholds (PPT) were assessed as test stimuli from the lower leg before, during and 5 min after delivering the conditioning tonic painful pressure stimulation. The tonic stimulus was delivered for 2 min by a custom-made spring-loaded finger pressure device applying a fixed pressure (2.2 kg) to the index finger nail. The pain intensity provoked by the tonic stimulus was continuously recorded on a 0–10 cm Visual Analog Scale (VAS). Results The median tonic pain stimulus intensity was 6.7 cm (interquartile range: 4.6–8.4 cm) on the 10 cm VAS. The mean PPT increased significantly (P = 0.034) by 55 ± 126 kPa from 518 ± 173 kPa before to 573 ± 228 kPa during conditioning stimulation. When analyzing the individual CPM responses (increases in PPT), a distribution of positive and negative CPM responders was observed with 69% of the individuals classified as positive CPM responders (increased PPTs = anti-nociceptive) and the rest as negative CPM responders (no or decreased PPTs = Pro-nociceptive). This particular responder distribution explains the large variation in the averaged CPM responses observed in many CPM studies. The strongest positive CPM response was an increase of 418 kPa and the strongest negative CPM response was a decrease of 140 kPa. Conclusions The present newly developed conditioning pain stimulator provides a simple, applicable tool for routine CPM assessment in clinical practice. Further, reporting averaged CPM effects should be replaced by categorizing volunteers/patients into anti-nociceptive and pro-nociceptive CPM groups. Implications The finger pressure device provided moderate-to-high pain intensities and was useful for inducing conditioning stimuli. Therefore, the finger pressure device could be a useful bed-side method for measuring CPM in clinical settings with limited time available. Future bed-side studies involving patient populations are warranted to determine the usefulness of the method.

Objectives Contemporary fear-avoidance models of chronic pain posit that fear of pain, and overgeneralization of fear to non-threatening stimuli is a potential pathway to chronic pain. While increasing experimental evidence supports this hypothesis, a comprehensive investigation requires testing in multiple modalities due to the diversity of symptomatology among individuals with chronic pain. In the present study we used an established tactile fear conditioning paradigm as an experimental model of allodynia and spontaneous pain fluctuations, to investigate whether stimulus generalization occurs resulting in fear of touch spreading to new locations. Methods In our paradigm, innocuous touch is presented either paired (predictable context) or unpaired (unpredictable context) with a painful electrocutaneous stimulus (pain-US). In the predictable context, vibrotactile stimulation to the index or little finger was paired with the pain-US (CS+), whilst stimulation of the other finger was never paired with pain (CS−). In the unpredictable context, vibrotactile stimulation to the index and little fingers of the opposite hand (CS1 and CS2) was unpaired with pain, but pain-USs occurred unpredictable during the intertrial interval. During the subsequent generalization phase, we tested the spreading of conditioned responses (self-reported fear of touch and pain expectancy) to the (middle and ring) fingers between the CS+ and CS−, and between the CS1 and CS2. Results Differential fear acquisition was evident in the predictable context from increased self-reported pain expectancy and self-reported fear for the CS + compared to the CS−. However, expectancy and fear ratings to the novel generalization stimuli (GS+ and GS−) were comparable to the responses elicited by the CS−. Participants reported equal levels of pain expectancy and fear to the CS1 and CS2 in the unpredictable context. However, the acquired fear did not spread in this context either: participants reported less pain expectancy and fear to the GS1 and GS2 than to the CS1 and CS2. As in our previous study, we did not observe differential acquisition in the startle responses. Conclusions Whilst our findings for the acquisition of fear of touch replicate the results from our previous study (Biggs et al., 2017), there was no evidence of fear generalization. We discuss the limitations of the present study, with a primary focus on procedural issues that were further investigated with post-hoc analyses, concluding that the present results do not show support for the hypothesis that stimulus generalization underlies spreading of fear of touch to new locations, and discuss how this may be the consequence of a context change that prevented transfer of acquisition.

Objectives The potential effects of physical activity and sedentary time on children’s increasing neck and shoulder pain are unclear. The aim of this cross-sectional study was to evaluate the associations between objectively measured physical activity or sedentary time and neck and shoulder pain in children. Methods Children (n=905; 10–15 years old) filled in an electronic questionnaire during school hours on the frequency of their neck and shoulder pain. Daytime moderate to vigorous physical activity and sedentary time were measured objectively with an ActiGraph accelerometer. A multinomial logistic regression was applied to study the associations. The results were adjusted for age, gender, body mass index and bedtime. Results Neck and shoulder pain experienced at least once a week was reported by 26.1% of children. A higher proportion of boys (45.9%) than girls (24.2%) achieved at least 60 min of moderate to vigorous physical activity/day (p<0.001). Girls were more sedentary than boys (sedentary time 66.4 vs. 63.1%) (p<0.001). Higher moderate to vigorous physical activity time was associated with a lower probability of experiencing neck and shoulder pain among boys, but not among girls. No association was found between sedentary time and neck and shoulder pain. Conclusions A quarter of the girls and boys reported frequent neck and shoulder pain. Boys achieved more moderate to vigorous physical activity than girls and higher moderate to vigorous physical activity was associated with a lower probability of having neck and shoulder pain, but only in boys. Neck and shoulder pain is the most common musculoskeletal pain and its prevalence is increasing. Preventing childhood pain is important, as neck and shoulder pain causes restrictions in daily living and is persistent to adulthood. Our study showed, that boys with more moderate to vigorous physical activity, had less weekly neck and shoulder pain symptoms. The present results are an addition to the list of benefits of physical activity and are valuable to, for example, healthcare personnel and teachers, who guide and teach children and adolescents. Families can benefit from new knowledge when considering supportive parenting activities. Municipalities can use the new information to design services for children or families.

Objectives The cardinal symptom of burning mouth syndrome (BMS) is long-lasting pain and comprehensive health-related quality of life (HRQL) assessments may estimate how well patients with BMS live in relation to their health issues. The aims of the study were to explore general and BMS-specific HRQL based on an HRQL model and to compare HRQL in patients with BMS and age-matched controls. Methods For this case-control study 56 female patients with BMS and 56 female controls completed the following: A general questionnaire with Global items for life satisfaction, general health and oral health; General Population-Clinical Outcomes in Routine Evaluation (GP-CORE); Hospital Anxiety and Depression Scale (HADS); and Oral Health Impact Profile-14 (OHIP-14). Patients with BMS completed additional questionnaires which included BMS-problem severity, a global item for ratings of overall severity perceptions measured by visual analog scale (VAS); and BMS-modified Multidimensional Pain Inventory-Swedish version (MPI-S). BMS-modified MPI-S includes the three subscales Pain severity, Interference and Social support. Results Patients with BMS scored worse on all global items, GP-CORE, HADS and OHIP-14 compared to controls and the differences were large. Patients with severe BMS problems, as defined by a median split on BMS-problem severity, scored worse on the BMS-modified MPI-S subscale Pain severity and the difference was large. Conclusions We found clearly impaired general HRQL in patients with BMS compared to controls. For specific HRQL, the severity of pain was worse among patients with higher overall BMS-problem severity. The HRQL model with global ratings together with physical, psychological and social concepts has capacity to increase comparability and validity of studies, however further evaluations of the measures are needed. The HRQL model may be used over time to increase the understanding of different HRQL aspects and their internal relationships. In clinical settings, with an increased knowledge of one´s own distinctive quality of life abilities and restrictions, the patients with BMS can be guided and supported to manage their long-lasting pain. The HRQL model may be an aid toward bridging distinctions between general and oral health to further encourage collaboration between medicine and odontology.

Objectives Stretching is an intervention often used in various kinds of rehabilitation protocols and the effects on pain sensitivity has sparsely been investigated, especially when addressing potential effects on pain. The objective is to investigate the immediate effects of an axial and peripheral prolonged stretch on pressure pain sensitivity (PPT) and temporal summation (TS) on local and distal sites in healthy subjects. Methods Twenty-two healthy volunteers were recruited to participate in this pilot study. Two prolonged stretching protocols were performed: low back and wrist extensors stretches. PPT and pinprick TS were measured pre- and post-intervention at local and remote sites. Repeated measures analysis of variance (ANOVA) was used to examine the effects and significance of the interventions. Results The low back stretch induced an increase in PPT for both local and remote sites, and the wrist stretch produced a PPT increase only at the local site. TS did not change. Conclusions Low back stretching induced an increase in PPT at both local and remote sites whereas the wrist stretch only increased PPT locally, suggesting hypoalgesia at these sites. Further studies are needed to confirm the effect and mechanisms using randomised, controlled and parallel study design. Considering that pain sensitivity is different than clinical pain, results are difficult to extrapolate to clinical practice. Future studies testing clinical pain are needed to better understand the clinical implication of these results.

Background Open radical nephrectomy and inferior vena cava exploration through a roof top incision involves significant peri-operative morbidity including severe postoperative pain. Although thoracic epidural analgesia provides excellent pain relief, recent trends suggest search for effective alternatives. Systemic morphine is often used as an alternative analgesic technique. However, it does not provide dynamic analgesia and can often impede recovery in patients undergoing major surgery on the abdomen. The authors present the first report of a novel analgesic regimen in this cohort with good outcomes. Methods Five patients undergoing open radical nephrectomy and inferior vena cava exploration received erector spinae plane infusion and intra thecal opioid analgesia at a tertiary care university teaching hospital. Outcomes included dynamic analgesia, length of hospital stay and complications Results Five adult patients undergoing major upper abdominal surgery, who refused thoracic epidural analgesia, received erector spinae plane infusion and intrathecal opioid analgesia. Patients reported effective dynamic analgesia, minimal use of rescue analgesia, early ambulation and enhanced recovery. Conclusion The novel regimen that avoids both epidural analgesia and systemic morphine can be an option in enabling enhanced recovery in this cohort.

Objectives Studies have shown that self-compassion plays a protective role against depression in women with chronic pain (CP). However, the majority of studies in CP have used the total score of the self-compassion scale (SCS), which have raised concerns due to potential overlap, not only between the uncompassionate self-responding factors and psychopathology, but also between self-compassion as a whole and other well-known psychological processes (e.g., mindfulness, acceptance, psychological flexibility). This calls for a more nuanced understanding of which components of (un)compassionate self-responding adds to better mental health in CP. Methods This study explores the unique contribution of compassionate and uncompassionate self-responding to depressive symptoms in women with CP undergoing pain consultation (n = 49). Results Correlation analyses suggest that compassionate self-responding only significantly correlates with progress in valued living, while the uncompassionate self-responding significantly correlates with pain fusion, pain avoidance, obstructions to valued living and depression. Multiple regression analysis showed that self-compassion contributes to depressive symptoms (R 2  = 8%) above and beyond pain intensity and disability (R 2  = 12%) and psychological (in) flexibility processes (R 2  = 31%), and uncompassionate (but not compassionate) self-responding uniquely contributes to depressive symptoms ( sr 2  = 18%). Conclusions Findings suggest that uncompassionate self-responding is a stronger contributor to depression in CP than compassionate self-responding. Clinical implications are further discussed.