Which patients with chronic low back pain respond favorably to multidisciplinary rehabilitation? A secondary analysis of a randomized controlled trial
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Claus Kjærgaard
,
Anne Mette Schmidt
Abstract
Objectives
The aim of this study was to identify prognostic variables at baseline associated with being responding favorably to multidisciplinary rehabilitation in patients with chronic low back pain (CLBP).
Methods
A responder analysis was conducted based on data from a randomized controlled trial with 26-week follow-up including 165 patients with CLBP treated at a Danish multidisciplinary rehabilitation center. Patients were dichotomized into responders and non-responders based on the outcome of a minimal clinically important difference of six points on the Oswestry Disability Index. The associations between prognostic variables and responders were analyzed using logistic regression.
Results
A total of 139 patients completed the study, of which 42% were classified as responders. Sex and employment status were statistically significant, with a decreased odds ratio (OR) of being a responder found for males compared to females (OR = 0.09, 95% CI = 0.02–0.48) and for being on temporary or permanent social benefits (OR = 0.28, 95% CI = 0.10–0.75) compared to being self-supporting or receiving retirement benefits. Statistically significant interaction (OR = 8.84, 95% CI = 1.11–70.12) was found between males and being on temporary or permanent social benefits.
Conclusions
In patients with CLBP, female patients as well as patients who were self-supporting or receiving retirement benefits were significantly more likely than male patients or patients on temporary or permanent social benefits to be a responder to multidisciplinary rehabilitation.
1 Introduction
In Denmark, as well as globally, chronic low back pain (CLBP) is a highly prevalent condition and the leading cause of years lived with disability [1,2]. Patients with CLBP represent a heterogeneous group with specific and non-specific low back pain diagnoses characterized by extensive variations in functional limitations and pain. The patient group is often affected by psychological and social challenges, severe sleep problems, and work- and leisure time-related limitations [3]. Thus, living with CLBP is influenced by complex interactions between multiple biological, psychological, and social factors [2,4].
Recognizing the complexities of CLBP has led to recommending the biopsychosocial model to understand and manage CLBP [5,6]. Multidisciplinary rehabilitation comprising a multifaceted intervention targeting biopsychosocial factors is thus recommended in patients with CLBP [5,6].
Healthcare resources are scarce and limited; multidisciplinary rehabilitation of patients with CLBP only has moderate effects [3,4]. Identification of prognostic variables in these patients that may affect the outcome of multidisciplinary rehabilitation may have considerable clinical impact. This means identifying the patients who may benefit from multidisciplinary rehabilitation (responders) and the patients who will not experience positive outcomes (non-responders).
The existing literature on prognostic variables as predictors of the outcome of multidisciplinary rehabilitation in patients with CLBP is inconsistent or contradictory [3,7–9]. This is probably due to heterogeneity in populations and multidisciplinary rehabilitation interventions as well as variations in the prognostic and outcome variables included [10]. However, psychological factors seem to be the most consistent prognostic variables of importance [3,7–9].
The objective of this study was to identify baseline prognostic variables among responders to multidisciplinary rehabilitation in patients with CLBP.
2 Methods
This is a responder analysis of a randomized controlled trial comparing the effectiveness of an existing multidisciplinary rehabilitation program and an integrated rehabilitation program for patients with CLBP at a Danish rehabilitation facility [11,12]. At the 26-week follow-up, there were no clinically or statistically significant differences between the patients in the two rehabilitation programs on the primary outcome using the Oswestry Disability Index (ODI) or the secondary outcomes [11], as the patients were regarded as one group.
2.1 Eligibility criteria
Inclusion and exclusion criteria have previously been published in detail [11].
The most important inclusion criteria were as follows: (1) LBP >12 months with or without sciatica and/or generalized pain identified by the International Classification of Diseases, version 10 codes, and (2) ODI score >21, indicating at least moderate disability. Patients were referred by general practitioners or hospital departments.
2.2 Data collection
Demographic data and patient-reported outcome measures were collected at the start of the rehabilitation program; patient-reported outcome measures were collected again at the 26-week follow-up. A secure electronic database was used to email questionnaires and store data. If not completed online, a research assistant provided an electronic tablet to the patient for questionnaire completion.
2.3 Outcome
The outcome was an improvement in disability as measured by the ODI version 2.1.a, which is considered a relevant core outcome in CLBP and recommended by the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials [13,14].
The ODI is a disease-specific 10-item scale with six statements expressing degrees of disability, and each item is scored on a 5-point scale. The ODI has shown good psychometric properties regarding validity and responsiveness in patients with CLBP [15].
The proportion of patients achieving a minimal clinically important difference (MCID) of six points on the ODI from baseline to 26-week follow-up [15] were categorized as responders [16].
2.4 Prognostic variables
Possible prognostic variables predicting improvement from multidisciplinary rehabilitation of patients with CLBP were selected based on the existing literature [3,7–9]. The collection of prognostic variables in the randomized controlled trial is described in Table 1.
Prognostic variables at baseline in patients with CLBP
| Variables | Measurement properties |
|---|---|
| Background variables: sex, age, marital status, smoking status, employment status, educational level | Questions comprising sex (male or female), age (years), marital status (married or single/widowed), smoking (yes or no), employment status (self-supporting/retirement benefits* or temporary/permanent social benefits**), and educational level (low/middle*** or high****) |
| Diagnosis | A rheumatologist examined the patients and investigated the electronic health records for ICD-10 diagnoses |
| Back pain intensity, last 14 days (average) | Numeric Rating Scale (NRS). An 11-point scale measuring pain intensity, where 0 = No pain and 10 = Worst pain imaginable [17] |
| Leg pain | Assessed as yes or no/do not know |
| Physical activity | Assessed by a questionnaire asking how many minutes per week were spent on physical activity, i.e., walking, bike riding, gardening, etc., and categorized according to WHO recommendations on physical activity <150 min, ≥150 min, or ≥300 min [18] |
| Health-related quality of life | Health-Related Quality of Life (HRQoL) was measured by the EQ-5D 5L questionnaire containing five elements with five response options. The final score has a 5-digit descriptor. Conversion to a Danish value set was calculated and ranged between 1 (optimal health) and −0.758 (worst health), and a higher score indicating better health. HRQoL was also measured as 0–100 (EQ VAS) with endpoints “Best health” and Worst health” [19] |
| Pain self-efficacy | The Pain Self-Efficacy Questionnaire (PSEQ) measures confidence in carrying out normal activities despite pain. Scores range from 0 to 60, with higher scores indicating higher pain self-efficacy [20] |
| Depression | The Major Depression Inventory (MDI) rates depression from 0 to 50, with higher scores indicating a higher degree of depression [21] |
*Ordinary employment or working in own home/early retirement; **Unemployed or flexible job/Social security, under education, sickness benefit, vocational rehabilitation or early retirement; ***Municipal primary and lower secondary school, upper secondary school/Skilled, lower and middle education; ****Higher education (>5 years); ICD-10, International Classification of Diseases 10th Revision; WHO, World Health Organization; EQ-5D 5L, EuroQol 5-Dimension 5-Level; EQ VAS, EuroQol Visual Analog Scale.
2.5 Statistical analysis
The proportion of patients classified as responders was analyzed. Patient characteristics, by responder/non-responder group and overall, were presented with frequencies (n) and percentages (%) and mean values and standard deviations (SD). To describe the associations between the prognostic variables and being a responder, a univariate logistic regression analysis was performed. Prognostic variables yielding p < 0.2 in the univariate analysis were included in the multivariate analysis. A multivariate analysis was performed to evaluate the magnitude of the prognostic variables. Crude and adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated using logistic regression analysis. The number of potential variables to be included in a multivariate analysis was based on the principle of at least 10 cases per variable [22,23]. The multivariate analysis model was examined for interactions between prognostic variables yielding p < 0.05. Patients with missing outcome data were excluded from the analysis.
All statistical analyses were performed using Stata 17 (StataCorp LP, College Station, TX, USA).
3 Results
Enrollment, reasons for exclusion, and number of patients with complete 26-week follow-up data are shown in Figure 1.
![Figure 1
Flowchart of patient enrolment in the randomized controlled trial. Permission granted to reproduce by Schmidt et al. [11].](/document/doi/10.1515/sjpain-2023-0139/asset/graphic/j_sjpain-2023-0139_fig_001.jpg)
Flowchart of patient enrolment in the randomized controlled trial. Permission granted to reproduce by Schmidt et al. [11].
A total of 139 patients had completed 26-week follow-up data and were included in the present study. Patient characteristics are presented in Table 2. Fifty-nine patients (42%) were classified as responders. Data show an equal distribution of age, level of education, and disability among responders and non-responders, respectively.
Patient characteristics at baseline, by responder group, and overall of patients with CLBP completing multidisciplinary rehabilitation
| Responders (n = 59) | Non-responders (n = 80) | Overall (n = 139) | |
|---|---|---|---|
| Sex (women), n (%) | 50 (85) | 51 (64) | 101 (73) |
| Age (years), mean (SD) | 52 (14) | 50 (11) | 51 (12) |
| Marital status, n (%) | |||
| Married | 40 (68) | 61 (76) | 101 (73) |
| Single/widowed | 19 (32) | 19 (24) | 38 (27) |
| Smokers, n (%) | |||
| Yes | 14 (24) | 26 (33) | 40 (29) |
| No | 45 (76) | 54 (67) | 99 (71) |
| Employment status, n (%)* | |||
| Self-supporting or retirement benefits | 27 (57) | 21 (34) | 48 (44) |
| Temporary or permanent social benefits | 20 (43) | 40 (66) | 60 (56) |
| Educational level, n (%)* | |||
| Low or middle (≤16 years of education) | 39 (83) | 54 (89) | 93 (86) |
| High (>16 years of education) | 8 (17) | 7 (11) | 15 (14) |
| Diagnosis, n (%) | |||
| Non-specific low back pain | 12 (20) | 19 (24) | 31 (22) |
| Stenosis | 7 (12) | 9 (11) | 16 (12) |
| Herniated disc | 21 (36) | 23 (29) | 44 (31) |
| Spondylosis | 19 (32) | 29 (36) | 48 (35) |
| Back pain intensity, last 14 days (average), NRS (0–10), mean (SD)** | 6 (2) | 6 (2) | 6 (2) |
| Leg pain, n (%) | |||
| Yes | 44 (75) | 60 (75) | 104 (75) |
| No/do not know | 15 (25) | 20 (25) | 35 (25) |
| Physical activity, WHO recommendation, n (%) | |||
| <150 min per week | 37 (63) | 52 (65) | 89 (64) |
| ≥150 < 300 per week | 10 (17) | 17 (21) | 27 (19) |
| ≥300 min per week | 12 (20) | 11 (14) | 23 (17) |
| Health-Related Quality of Life** | |||
| EQ-5D 5L Index (−0.758 to 1), median | 0.705 | 0.573 | 0.641 (0.443) |
| EQ-5D 5L Index (−0.758 to 1), IQR | (0.404; 0.801) | (0.304; 0.777) | (0.347; 0.790) |
| EQ VAS (0–100), mean (SD) | 51 (18) | 48 (21) | 49 (20) |
| Pain Self-Efficacy, PSEQ (0–60), mean (SD) | 31 (11) | 29 (11) | 30 (11) |
| Depression, MDI (0–50), mean (SD) | 17 (10) | 20 (11) | 19 (10) |
| Disability, ODI (0–100), mean (SD)** | 40 (9) | 40 (14) | 40 (12) |
N: number of subjects; SD: standard deviation; NRS: numeric rating scale; WHO: World Health Organization; EQ-5D 5L: EuroQol 5-Dimension 5-Level; IQR: inter quartile range; EQ VAS: EuroQol Visual Analog Scale; PSEQ: pain self-efficacy questionnaire; MDI: major depression inventory; ODI: oswestry disability index; *: 31 missing due to technical database problems; **: 2 missing.
The univariate logistic regression analysis between the prognostic variables and being a responder is presented in Table 3. Significant differences between responders and non-responders were found (prognostic variables yielding p < 0.2) for sex, employment status, pain self-efficacy, and depression. There were lower odds of being a responder for males compared to females (OR = 0.32, 95% CI = 0.14–0.74), being on temporary or permanent social benefits compared to being self-supporting or receiving retirement benefits (OR = 0.39, 95% CI = 0.18–0.85), having a lower pain self-efficacy score (OR = 1.04, 95% CI = 1.01–1.08), as well as having a higher depression score (OR = 0.97, 95% CI = 0.94–1.00).
Univariate logistic regression analysis of the associations (OR) between potential prognostic variables and being a responder to multidisciplinary rehabilitation for CLBP
| Prognostic variables | Crude | |
|---|---|---|
| OR (95% CI) | p-Value | |
| Sex | ||
| Female | 1 (reference) | (ref) |
| Male | 0.32 (0.14–0.74) | 0.01 |
| Age | 1.01 (0.99–1.04) | 0.34 |
| Marital status | ||
| Married | 1 (reference) | (ref) |
| Single/widowed | 1.53 (0.72–3.23) | 0.27 |
| Smokers | ||
| Yes | 1 (reference) | (ref) |
| No | 1.55 (0.72–3.31) | 0.26 |
| Employment status* | ||
| Self-supporting or retirement benefits | 1 (reference) | (ref) |
| Temporary or permanent social benefits | 0.39 (0.18–0.85) | 0.02 |
| Educational level* | ||
| Low or middle (≤16 years of education) | 1 (reference) | (ref) |
| High (>16 years of education) | 1.58 (0.53–4.73) | 0.41 |
| Diagnosis | ||
| Non-specific low back pain | 1 (reference) | (ref) |
| Stenosis | 1.23 (0.36–4.19) | 0.74 |
| Herniated disc | 1.45 (0.57–3.68) | 0.44 |
| Spondylosis | 1.04 (0.41–2.62) | 0.94 |
| Back pain intensity, last 14 days (average)** | 1.02 (0.85–1.24) | 0.80 |
| Leg pain | ||
| Yes | 1 (reference) | (ref) |
| No/Do not know | 1.02 (0.47–2.21) | 0.96 |
| Physical activity, WHO recommendation | ||
| <150 min per week | 1 (reference) | (ref) |
| ≥150 < 300 per week | 0.83 (0.34–2.01) | 0.67 |
| ≥300 min per week | 1.53 (0.61–3.85) | 0.36 |
| Health-Related Quality of Life** | ||
| EQ-5D 5L Index (−0.758 to 1) | 1.88 (0.56–6.31) | 0.31 |
| EQ-5D 5L VAS (0–100) | 1.01 (0.99–1.03) | 0.31 |
| Pain Self-Efficacy, PSEQ (0–60) | 1.04 (1.01–1.08) | 0.02 |
| Depression, MDI (0–50) | 0.97 (0.94–1.00) | 0.05 |
OR: Odds Ratio; WHO: World Health Organization; EQ-5D 5L: EuroQol 5-Dimension 5-Level; EQ VAS: EuroQol Visual Analog Scale; PSEQ: pain self-efficacy questionnaire; MDI: major depression inventory; ODI: oswestry disability index; *: 31 missing due to technical database problems, **: 2 missing due to randomly missed answers.
The results of the multivariate logistic regression analysis performed on the prognostic variables yielding p < 0.2 in the univariate logistic regression are presented in Table 4. Results for sex and employment status were statistically significant in the multivariate logistic regression. Significantly decreased odds of being a responder were found for males compared to females (OR = 0.09, 95% CI = 0.02–0.48) if both were self-supporting or receiving retirement benefits and equal in scores of pain self-efficacy and depression, indicating that males had 91% lesser odds of being a responder to multidisciplinary rehabilitation than females in that combination. In addition, being on temporary or permanent social benefits significantly decreased the odds of being a responder by 72% (OR = 0.28, 95% CI = 0.10–0.75) compared to being self-supporting or receiving retirement benefits if patients were females and equal in the two other variables. A statistically significant interaction (OR = 8.84, 95% CI = 1.11–70.12) was found between males and being on temporary or permanent social benefits, indicating that males have 20% lower odds of being a responder compared to females if both received temporary or permanent social benefits and had equal pain self-efficacy and depression scores.
Multivariate logistic regression for the associations (OR) between potential prognostic variables and being a responder to multidisciplinary rehabilitation for CLBP
| Prognostic variables | Adjusted | |
|---|---|---|
| OR (95% CI) | p-Value | |
| Sex | ||
| Female | 1 (reference) | (ref) |
| Male | 0.09 (0.02–0.48) | 0.01 |
| Employment status | ||
| Self-supporting or retirement benefits | 1 (reference) | (ref) |
| Temporary or permanent social benefits | 0.28 (0.10–0.75) | 0.01 |
| Sex x Employment status | ||
| Male x Temporary or permanent social benefits | 8.84 (1.11–70.12) | 0.04 |
| Pain Self-Efficacy, PSEQ (0–60) | 1.02 (0.98–1.06) | 0.31 |
| Depression, MDI (0–50) | 1.00 (0.96–1.05) | 0.98 |
OR: Odds ratio; x: Interaction; PSEQ: pain self-efficacy questionnaire; MDI: major depression inventory.
4 Discussion
This responder analysis found that females and being self-supporting or on retirement benefits were statistically significant prognostic variables for a clinically meaningful outcome of multidisciplinary rehabilitation.
Females had significantly higher odds of being a responder, which was generally reported as a weaker association in most of the existing literature [3,7,8], although some studies have found results similar to ours [24,25]. The significant difference in odds of being a responder in our study depended on employment status, which is also inconsistent with most of the existing literature [3,7,8]. However, some studies reported results similar to ours [26,27].
In general, comparison with the existing literature is difficult due to various inconsistencies. Numerous studies including systematic reviews and meta-analyses [3,7,8] set out to examine prognostic variables associated with being a responder. In essence, they describe that results may be unclear or that the specific prognostic variables may have a lower association than hypothesized. A higher pain score at baseline has, e.g., been found both predictive for worse and better outcomes [7,8]. Similarly, work-related factors have been found to be predictive [8], although the effect has been minor [3,7]. More commonly, psychological factors have been found predictive [3,8], though not consistently in the existing literature [7]. In this study, the psychological factors were not found statistically significant, but the small sample size may imply a risk of type II error.
There may be several reasons for the inconsistencies reported in the existing literature. First, although the biopsychosocial model is widely recommended, the components and weights of the components in multidisciplinary rehabilitation may vary considerably, i.e., from the focus on returning to work, addressing psychological factors, or improvement of physical aspects. Furthermore, patients with CLBP are heterogeneous, and samples of patients may thus differ between studies with regard to patient characteristics and cultures [3,7]. Finally, methods in responder analysis are found to vary greatly in outcome measures, categorization of prognostic variables, and MCID cut-off scores, challenging direct comparisons [10].
In the present study, 59 out of 139 patients (42%) showed a clinically meaningful outcome following the multidisciplinary rehabilitation program and were classified as responders. This number is based on the recommended cut-off score of a minimum six-point decrease in the ODI [15]. Selecting a different cut-off score of at least six points would have led to a different estimated proportion of responders and, thereby, to different associations between prognostic variables and being a responder to rehabilitation. When comparing definitions of response in responder analyses, 20 different definitions were used in 28 randomized controlled trials [10]. This emphasizes the importance of standardized responder criteria. The ODI was used as it is condition-specific for CLBP compared to, i.e., the EQ-5D as a generic patient-reported outcome measure, while also considered a relevant core outcome in CLBP and recommended by the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials [13,14].
The results of the current study suggest future research is needed into differentiated and individualized rehabilitation programs targeting specific needs according to sex as well as employment status for patients with CLBP.
5 Strengths and limitations
This study has several strengths. First, the assessment of prognostic variables at baseline was unaffected by the knowledge of the outcome. Second, a low number of missing values were observed, which minimizes the risk of attrition bias. Two variables, employment status and educational level, had approximately 25% missing values due to technical issues in the database, which was therefore considered missing at random and thus not introducing bias. Third, the methods were decided a priori, which reduced the risk of data-driven results. Fourth, clinically meaningful improvements reported in the literature [15] were used as cut-off levels for the logistic regression analysis.
This study also has important limitations, which should be kept in mind when interpreting the findings. First, the sample size was relatively small, which limits the statistical power and the certainty of the estimates. Second, the study was based on data from a randomized controlled trial conducted at a rehabilitation center in Denmark, with a sample of patients attending either an existing 4-week inpatient multidisciplinary rehabilitation program or an integrated program with the same content over a 14-week period. Whether our results may be generalized to other patients with CLBP is unknown, and the generalizability may be affected by the exclusion of 96 eligible patients due to motivational factors or preferences for the existing program; however, no significant differences were found in baseline characteristics between those excluded and those included (data not presented). Third, the major issue of using a logistic regression model is choosing the correct variables for the model [28]. As this study is a secondary analysis where the variables available for the logistic regression are defined by the original trial [11], the inclusion of other variables may have yielded different results [11]. Fourth, though a cut-off score has previously been demonstrated to discriminate well between responders and non-responders, some misclassification of responder status may exist as patient-reported outcome measures are preferably analyzed on their own metric [29].
6 Conclusion
This study shows that female patients as well as patients who were self-supporting or receiving retirement benefits were significantly more likely than male patients or patients on temporary or permanent social benefits to be responders and thus have a clinically meaningful outcome of attending multidisciplinary rehabilitation for patients with CLBP. However, the study has limitations that may impact the generalizability of these findings to all patients with CLBP. Further research is needed to validate these observations and provide more robust guidance for clinicians.
Acknowledgements
The authors express their gratitude to all patients, providers, administrative, and management staff at Sano who facilitated the conduct of this trial. Additionally, the authors thank Johan Riisgaard Laursen, MSc. PT, for his assistance with data extraction.
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Research ethics: The Central Denmark Region Committees on Biomedical and Research Ethics approved the trial (journal number: 1-10-72-117-16).
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Informed consent: Informed consent was obtained from all individuals included in this study, or their legal guardians or wards.
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Author contributions: The authors have accepted responsibility for the entire content of this manuscript and approved its submission.
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Competing intersets: Authors state no conflict of interest.
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Research funding: Authors state no funding.
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Data availability: The raw data can be obtained on request from the corresponding author.
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© 2024 the author(s), published by De Gruyter
This work is licensed under the Creative Commons Attribution 4.0 International License.
Articles in the same Issue
- Editorial Comment
- From pain to relief: Exploring the consistency of exercise-induced hypoalgesia
- Christmas greetings 2024 from the Editor-in-Chief
- Original Articles
- The Scandinavian Society for the Study of Pain 2022 Postgraduate Course and Annual Scientific (SASP 2022) Meeting 12th to 14th October at Rigshospitalet, Copenhagen
- Comparison of ultrasound-guided continuous erector spinae plane block versus continuous paravertebral block for postoperative analgesia in patients undergoing proximal femur surgeries
- Clinical Pain Researches
- The effect of tourniquet use on postoperative opioid consumption after ankle fracture surgery – a retrospective cohort study
- Changes in pain, daily occupations, lifestyle, and health following an occupational therapy lifestyle intervention: a secondary analysis from a feasibility study in patients with chronic high-impact pain
- Tonic cuff pressure pain sensitivity in chronic pain patients and its relation to self-reported physical activity
- Reliability, construct validity, and factorial structure of a Swedish version of the medical outcomes study social support survey (MOS-SSS) in patients with chronic pain
- Hurdles and potentials when implementing internet-delivered Acceptance and commitment therapy for chronic pain: a retrospective appraisal using the Quality implementation framework
- Exploring the outcome “days with bothersome pain” and its association with pain intensity, disability, and quality of life
- Fatigue and cognitive fatigability in patients with chronic pain
- The Swedish version of the pain self-efficacy questionnaire short form, PSEQ-2SV: Cultural adaptation and psychometric evaluation in a population of patients with musculoskeletal disorders
- Pain coping and catastrophizing in youth with and without cerebral palsy
- Neuropathic pain after surgery – A clinical validation study and assessment of accuracy measures of the 5-item NeuPPS scale
- Translation, contextual adaptation, and reliability of the Danish Concept of Pain Inventory (COPI-Adult (DK)) – A self-reported outcome measure
- Cosmetic surgery and associated chronic postsurgical pain: A cross-sectional study from Norway
- The association of hemodynamic parameters and clinical demographic variables with acute postoperative pain in female oncological breast surgery patients: A retrospective cohort study
- Healthcare professionals’ experiences of interdisciplinary collaboration in pain centres – A qualitative study
- Effects of deep brain stimulation and verbal suggestions on pain in Parkinson’s disease
- Painful differences between different pain scale assessments: The outcome of assessed pain is a matter of the choices of scale and statistics
- Prevalence and characteristics of fibromyalgia according to three fibromyalgia diagnostic criteria: A secondary analysis study
- Sex moderates the association between quantitative sensory testing and acute and chronic pain after total knee/hip arthroplasty
- Tramadol-paracetamol for postoperative pain after spine surgery – A randomized, double-blind, placebo-controlled study
- Cancer-related pain experienced in daily life is difficult to communicate and to manage – for patients and for professionals
- Making sense of pain in inflammatory bowel disease (IBD): A qualitative study
- Patient-reported pain, satisfaction, adverse effects, and deviations from ambulatory surgery pain medication
- Does pain influence cognitive performance in patients with mild traumatic brain injury?
- Hypocapnia in women with fibromyalgia
- Application of ultrasound-guided thoracic paravertebral block or intercostal nerve block for acute herpes zoster and prevention of post-herpetic neuralgia: A case–control retrospective trial
- Translation and examination of construct validity of the Danish version of the Tampa Scale for Kinesiophobia
- A positive scratch collapse test in anterior cutaneous nerve entrapment syndrome indicates its neuropathic character
- ADHD-pain: Characteristics of chronic pain and association with muscular dysregulation in adults with ADHD
- The relationship between changes in pain intensity and functional disability in persistent disabling low back pain during a course of cognitive functional therapy
- Intrathecal pain treatment for severe pain in patients with terminal cancer: A retrospective analysis of treatment-related complications and side effects
- Psychometric evaluation of the Danish version of the Pain Self-Efficacy Questionnaire in patients with subacute and chronic low back pain
- Dimensionality, reliability, and validity of the Finnish version of the pain catastrophizing scale in chronic low back pain
- To speak or not to speak? A secondary data analysis to further explore the context-insensitive avoidance scale
- Pain catastrophizing levels differentiate between common diseases with pain: HIV, fibromyalgia, complex regional pain syndrome, and breast cancer survivors
- Prevalence of substance use disorder diagnoses in patients with chronic pain receiving reimbursed opioids: An epidemiological study of four Norwegian health registries
- Pain perception while listening to thrash heavy metal vs relaxing music at a heavy metal festival – the CoPainHell study – a factorial randomized non-blinded crossover trial
- Observational Studies
- Cutaneous nerve biopsy in patients with symptoms of small fiber neuropathy: a retrospective study
- The incidence of post cholecystectomy pain (PCP) syndrome at 12 months following laparoscopic cholecystectomy: a prospective evaluation in 200 patients
- Associations between psychological flexibility and daily functioning in endometriosis-related pain
- Relationship between perfectionism, overactivity, pain severity, and pain interference in individuals with chronic pain: A cross-lagged panel model analysis
- Access to psychological treatment for chronic cancer-related pain in Sweden
- Validation of the Danish version of the knowledge and attitudes survey regarding pain
- Associations between cognitive test scores and pain tolerance: The Tromsø study
- Healthcare experiences of fibromyalgia patients and their associations with satisfaction and pain relief. A patient survey
- Video interpretation in a medical spine clinic: A descriptive study of a diverse population and intervention
- Role of history of traumatic life experiences in current psychosomatic manifestations
- Social determinants of health in adults with whiplash associated disorders
- Which patients with chronic low back pain respond favorably to multidisciplinary rehabilitation? A secondary analysis of a randomized controlled trial
- A preliminary examination of the effects of childhood abuse and resilience on pain and physical functioning in patients with knee osteoarthritis
- Differences in risk factors for flare-ups in patients with lumbar radicular pain may depend on the definition of flare
- Real-world evidence evaluation on consumer experience and prescription journey of diclofenac gel in Sweden
- Patient characteristics in relation to opioid exposure in a chronic non-cancer pain population
- Topical Reviews
- Bridging the translational gap: adenosine as a modulator of neuropathic pain in preclinical models and humans
- What do we know about Indigenous Peoples with low back pain around the world? A topical review
- The “future” pain clinician: Competencies needed to provide psychologically informed care
- Systematic Reviews
- Pain management for persistent pain post radiotherapy in head and neck cancers: systematic review
- High-frequency, high-intensity transcutaneous electrical nerve stimulation compared with opioids for pain relief after gynecological surgery: a systematic review and meta-analysis
- Reliability and measurement error of exercise-induced hypoalgesia in pain-free adults and adults with musculoskeletal pain: A systematic review
- Noninvasive transcranial brain stimulation in central post-stroke pain: A systematic review
- Short Communications
- Are we missing the opioid consumption in low- and middle-income countries?
- Association between self-reported pain severity and characteristics of United States adults (age ≥50 years) who used opioids
- Could generative artificial intelligence replace fieldwork in pain research?
- Skin conductance algesimeter is unreliable during sudden perioperative temperature increases
- Original Experimental
- Confirmatory study of the usefulness of quantum molecular resonance and microdissectomy for the treatment of lumbar radiculopathy in a prospective cohort at 6 months follow-up
- Pain catastrophizing in the elderly: An experimental pain study
- Improving general practice management of patients with chronic musculoskeletal pain: Interdisciplinarity, coherence, and concerns
- Concurrent validity of dynamic bedside quantitative sensory testing paradigms in breast cancer survivors with persistent pain
- Transcranial direct current stimulation is more effective than pregabalin in controlling nociceptive and anxiety-like behaviors in a rat fibromyalgia-like model
- Paradox pain sensitivity using cuff pressure or algometer testing in patients with hemophilia
- Physical activity with person-centered guidance supported by a digital platform or with telephone follow-up for persons with chronic widespread pain: Health economic considerations along a randomized controlled trial
- Measuring pain intensity through physical interaction in an experimental model of cold-induced pain: A method comparison study
- Pharmacological treatment of pain in Swedish nursing homes: Prevalence and associations with cognitive impairment and depressive mood
- Neck and shoulder pain and inflammatory biomarkers in plasma among forklift truck operators – A case–control study
- The effect of social exclusion on pain perception and heart rate variability in healthy controls and somatoform pain patients
- Revisiting opioid toxicity: Cellular effects of six commonly used opioids
- Letter to the Editor
- Post cholecystectomy pain syndrome: Letter to Editor
- Response to the Letter by Prof Bordoni
- Response – Reliability and measurement error of exercise-induced hypoalgesia
- Is the skin conductance algesimeter index influenced by temperature?
- Skin conductance algesimeter is unreliable during sudden perioperative temperature increase
- Corrigendum
- Corrigendum to “Chronic post-thoracotomy pain after lung cancer surgery: a prospective study of preoperative risk factors”
- Obituary
- A Significant Voice in Pain Research Björn Gerdle in Memoriam (1953–2024)
Articles in the same Issue
- Editorial Comment
- From pain to relief: Exploring the consistency of exercise-induced hypoalgesia
- Christmas greetings 2024 from the Editor-in-Chief
- Original Articles
- The Scandinavian Society for the Study of Pain 2022 Postgraduate Course and Annual Scientific (SASP 2022) Meeting 12th to 14th October at Rigshospitalet, Copenhagen
- Comparison of ultrasound-guided continuous erector spinae plane block versus continuous paravertebral block for postoperative analgesia in patients undergoing proximal femur surgeries
- Clinical Pain Researches
- The effect of tourniquet use on postoperative opioid consumption after ankle fracture surgery – a retrospective cohort study
- Changes in pain, daily occupations, lifestyle, and health following an occupational therapy lifestyle intervention: a secondary analysis from a feasibility study in patients with chronic high-impact pain
- Tonic cuff pressure pain sensitivity in chronic pain patients and its relation to self-reported physical activity
- Reliability, construct validity, and factorial structure of a Swedish version of the medical outcomes study social support survey (MOS-SSS) in patients with chronic pain
- Hurdles and potentials when implementing internet-delivered Acceptance and commitment therapy for chronic pain: a retrospective appraisal using the Quality implementation framework
- Exploring the outcome “days with bothersome pain” and its association with pain intensity, disability, and quality of life
- Fatigue and cognitive fatigability in patients with chronic pain
- The Swedish version of the pain self-efficacy questionnaire short form, PSEQ-2SV: Cultural adaptation and psychometric evaluation in a population of patients with musculoskeletal disorders
- Pain coping and catastrophizing in youth with and without cerebral palsy
- Neuropathic pain after surgery – A clinical validation study and assessment of accuracy measures of the 5-item NeuPPS scale
- Translation, contextual adaptation, and reliability of the Danish Concept of Pain Inventory (COPI-Adult (DK)) – A self-reported outcome measure
- Cosmetic surgery and associated chronic postsurgical pain: A cross-sectional study from Norway
- The association of hemodynamic parameters and clinical demographic variables with acute postoperative pain in female oncological breast surgery patients: A retrospective cohort study
- Healthcare professionals’ experiences of interdisciplinary collaboration in pain centres – A qualitative study
- Effects of deep brain stimulation and verbal suggestions on pain in Parkinson’s disease
- Painful differences between different pain scale assessments: The outcome of assessed pain is a matter of the choices of scale and statistics
- Prevalence and characteristics of fibromyalgia according to three fibromyalgia diagnostic criteria: A secondary analysis study
- Sex moderates the association between quantitative sensory testing and acute and chronic pain after total knee/hip arthroplasty
- Tramadol-paracetamol for postoperative pain after spine surgery – A randomized, double-blind, placebo-controlled study
- Cancer-related pain experienced in daily life is difficult to communicate and to manage – for patients and for professionals
- Making sense of pain in inflammatory bowel disease (IBD): A qualitative study
- Patient-reported pain, satisfaction, adverse effects, and deviations from ambulatory surgery pain medication
- Does pain influence cognitive performance in patients with mild traumatic brain injury?
- Hypocapnia in women with fibromyalgia
- Application of ultrasound-guided thoracic paravertebral block or intercostal nerve block for acute herpes zoster and prevention of post-herpetic neuralgia: A case–control retrospective trial
- Translation and examination of construct validity of the Danish version of the Tampa Scale for Kinesiophobia
- A positive scratch collapse test in anterior cutaneous nerve entrapment syndrome indicates its neuropathic character
- ADHD-pain: Characteristics of chronic pain and association with muscular dysregulation in adults with ADHD
- The relationship between changes in pain intensity and functional disability in persistent disabling low back pain during a course of cognitive functional therapy
- Intrathecal pain treatment for severe pain in patients with terminal cancer: A retrospective analysis of treatment-related complications and side effects
- Psychometric evaluation of the Danish version of the Pain Self-Efficacy Questionnaire in patients with subacute and chronic low back pain
- Dimensionality, reliability, and validity of the Finnish version of the pain catastrophizing scale in chronic low back pain
- To speak or not to speak? A secondary data analysis to further explore the context-insensitive avoidance scale
- Pain catastrophizing levels differentiate between common diseases with pain: HIV, fibromyalgia, complex regional pain syndrome, and breast cancer survivors
- Prevalence of substance use disorder diagnoses in patients with chronic pain receiving reimbursed opioids: An epidemiological study of four Norwegian health registries
- Pain perception while listening to thrash heavy metal vs relaxing music at a heavy metal festival – the CoPainHell study – a factorial randomized non-blinded crossover trial
- Observational Studies
- Cutaneous nerve biopsy in patients with symptoms of small fiber neuropathy: a retrospective study
- The incidence of post cholecystectomy pain (PCP) syndrome at 12 months following laparoscopic cholecystectomy: a prospective evaluation in 200 patients
- Associations between psychological flexibility and daily functioning in endometriosis-related pain
- Relationship between perfectionism, overactivity, pain severity, and pain interference in individuals with chronic pain: A cross-lagged panel model analysis
- Access to psychological treatment for chronic cancer-related pain in Sweden
- Validation of the Danish version of the knowledge and attitudes survey regarding pain
- Associations between cognitive test scores and pain tolerance: The Tromsø study
- Healthcare experiences of fibromyalgia patients and their associations with satisfaction and pain relief. A patient survey
- Video interpretation in a medical spine clinic: A descriptive study of a diverse population and intervention
- Role of history of traumatic life experiences in current psychosomatic manifestations
- Social determinants of health in adults with whiplash associated disorders
- Which patients with chronic low back pain respond favorably to multidisciplinary rehabilitation? A secondary analysis of a randomized controlled trial
- A preliminary examination of the effects of childhood abuse and resilience on pain and physical functioning in patients with knee osteoarthritis
- Differences in risk factors for flare-ups in patients with lumbar radicular pain may depend on the definition of flare
- Real-world evidence evaluation on consumer experience and prescription journey of diclofenac gel in Sweden
- Patient characteristics in relation to opioid exposure in a chronic non-cancer pain population
- Topical Reviews
- Bridging the translational gap: adenosine as a modulator of neuropathic pain in preclinical models and humans
- What do we know about Indigenous Peoples with low back pain around the world? A topical review
- The “future” pain clinician: Competencies needed to provide psychologically informed care
- Systematic Reviews
- Pain management for persistent pain post radiotherapy in head and neck cancers: systematic review
- High-frequency, high-intensity transcutaneous electrical nerve stimulation compared with opioids for pain relief after gynecological surgery: a systematic review and meta-analysis
- Reliability and measurement error of exercise-induced hypoalgesia in pain-free adults and adults with musculoskeletal pain: A systematic review
- Noninvasive transcranial brain stimulation in central post-stroke pain: A systematic review
- Short Communications
- Are we missing the opioid consumption in low- and middle-income countries?
- Association between self-reported pain severity and characteristics of United States adults (age ≥50 years) who used opioids
- Could generative artificial intelligence replace fieldwork in pain research?
- Skin conductance algesimeter is unreliable during sudden perioperative temperature increases
- Original Experimental
- Confirmatory study of the usefulness of quantum molecular resonance and microdissectomy for the treatment of lumbar radiculopathy in a prospective cohort at 6 months follow-up
- Pain catastrophizing in the elderly: An experimental pain study
- Improving general practice management of patients with chronic musculoskeletal pain: Interdisciplinarity, coherence, and concerns
- Concurrent validity of dynamic bedside quantitative sensory testing paradigms in breast cancer survivors with persistent pain
- Transcranial direct current stimulation is more effective than pregabalin in controlling nociceptive and anxiety-like behaviors in a rat fibromyalgia-like model
- Paradox pain sensitivity using cuff pressure or algometer testing in patients with hemophilia
- Physical activity with person-centered guidance supported by a digital platform or with telephone follow-up for persons with chronic widespread pain: Health economic considerations along a randomized controlled trial
- Measuring pain intensity through physical interaction in an experimental model of cold-induced pain: A method comparison study
- Pharmacological treatment of pain in Swedish nursing homes: Prevalence and associations with cognitive impairment and depressive mood
- Neck and shoulder pain and inflammatory biomarkers in plasma among forklift truck operators – A case–control study
- The effect of social exclusion on pain perception and heart rate variability in healthy controls and somatoform pain patients
- Revisiting opioid toxicity: Cellular effects of six commonly used opioids
- Letter to the Editor
- Post cholecystectomy pain syndrome: Letter to Editor
- Response to the Letter by Prof Bordoni
- Response – Reliability and measurement error of exercise-induced hypoalgesia
- Is the skin conductance algesimeter index influenced by temperature?
- Skin conductance algesimeter is unreliable during sudden perioperative temperature increase
- Corrigendum
- Corrigendum to “Chronic post-thoracotomy pain after lung cancer surgery: a prospective study of preoperative risk factors”
- Obituary
- A Significant Voice in Pain Research Björn Gerdle in Memoriam (1953–2024)
