Localized low back pain and low back pain as part of widespread musculoskeletal pain: two different disorders? A cross-sectional population study

Considerations beyond spine pain: do different co-occurring lower body joint pains differentially influence physical function and quality of life ratings?

BACKGROUND

Patients seeking medical care for back pain often have coexisting painful joints and the effects of different combinations and number of coexisting pain sites (hip, knee, foot/ankle) to back pain on physical function domains and quality of life rating are not yet established. The purpose of this study was to determine the differences in functional outcomes and QOL among individuals with back pain who have concurrent additional pain sites or no pain sites.

METHODS

Data from the Osteoarthritis Initiative (OAI) cohort were used for this cross-sectional analysis. Men and women aged 45-79 years with back pain were binned into nine groups by presence or not of coexisting hip, knee, ankle/foot pain and combinations of these sites (N = 1,642). Healthy controls reported no joint pain. Main outcomes included Knee Injury and Osteoarthritis Outcome score (KOOS; quality of life and function-sports-and-recreation), Western Ontario McMaster Universities Osteoarthritis Index (WOMAC; Activities of Daily Living, Pain), Medical Outcomes Short Form-12 (SF-12) Physical Component score, and self-reported function in last 7-30 days (lifting 25-pound objects, housework). 20-m and 400-m walk times and gait speed and repeated chair rise test times were collected.

RESULTS

Compared to back pain alone, pain at all five sites was associated with 39%-86% worse KOOS, WOMAC, and SF-12 scores (p < .0001). Back-Hip and Back-Knee did not produce worse scores than Back pain alone, but Back-Hip-Knee and Back-Knee-Ankle/Foot did. The 20-m, 400-m walk, and repeated chair times were worse among individuals with pain at all five sites. Additional hip and knee sites to back pain, but not ankle/foot, worsened performance-based walk times and chair rise scores.

CONCLUSIONS

The number and type of coexistent lower body musculoskeletal pain among patients with back pain may be associated with perceived and performance-based assessments. Management plans that efficiently simultaneously address back and additional coexistent pain sites may maximize treatment functional benefits, address patient functional goals in life and mitigate disability.

Temporal stability in the prevalence and pattern of co-occurring musculoskeletal pain among people with persistent low back pain: population-based data from the Norwegian HUNT Study, 1995 to 2019

ABSTRACT

People with persistent low back pain (LBP) often report co-occurring persistent musculoskeletal (MSK) pain in other body regions that may influence prognosis as well as treatment approaches and outcomes. This study describes the prevalence and patterns of co-occurring persistent MSK pain among people with persistent LBP based on consecutive cross-sectional studies over 3 decades in the population-based HUNT Study, Norway. The analyses comprised 15,375 participants in HUNT2 (1995-1997), 10,024 in HUNT3 (2006-2008), and 10,647 in HUNT4 (2017-2019) who reported persistent LBP. Overall, ∼90% of participants in each of the HUNT surveys with persistent LBP reported persistent co-occurring MSK pain in other body sites. The age-standardized prevalence of the most common co-occurring MSK pain sites was consistent across the 3 surveys: 64% to 65% report co-occurring neck pain, 62% to 67% report shoulder pain, and 53% to 57% report hip or thigh pain. Using latent class analysis (LCA), we identified 4 distinct patterns of persistent LBP phenotypes that were consistent across the 3 surveys: (1) "LBP only," (2) "LBP with neck or shoulder pain," (3) "LBP with lower extremity or wrist or hand pain," and (4) "LBP with multisite pain," with conditional item response probabilities of 34% to 36%, 30% to 34%, 13% to 17%, and 16% to 20%, respectively. In conclusion, 9 of 10 adults in this Norwegian population with persistent LBP report co-occurring persistent MSK pain, most commonly in the neck, shoulders, and hips or thighs. We identified 4 LCA-derived LBP phenotypes of distinct MSK pain site patterns. In the population, both the prevalence and pattern of co-occurring MSK pain and the distinct phenotypic MSK pain patterns seem stable over decades.

An Exploration of the Influence of Non-Biomechanical Factors on Lifting-Related LBP

Objective: The primary objective was to compare non-biomechanical factors between manual workers with and without a history of LBP related to lifting. A secondary objective was to investigate associations between the change in pain intensity during repeated lifting (termed pain ramp) and non-biomechanical factors tested in the LBP group. Methods: Manual workers currently in lifting occupations with and without a history of lifting-related LBP were recruited (21 LBP and 20 noLBP) and took part in a repeated (100) lift task. A series of non-biomechanical factors, including psychological, work-related, lifestyle, whole health and psychophysical factors, were collected. Psychophysical factors (pressure pain thresholds (PPTs) and fatigue) were also measured at different time points. Associations between pain ramp during lifting and non-biomechanical factors were investigated with linear regression. Results: The LBP group reported worse perceived sleep quality, more musculoskeletal pain sites other than LBP and greater symptoms related to gastrointestinal complaints and pseudo-neurology compared to the group with no history of LBP. The group with LBP were also slightly more worried about the lifting task and felt more fatigued at the end of the lifting task. The feeling of fatigue during lifting was positively associated with pain ramp in the LBP group. Anxiety and gastrointestinal complaints were weakly negatively associated with pain ramp during lifting. Conclusions: The group differences of poorer perceived sleep, greater non-specific health complaints, slightly more worry about the lifting task and more perceived fatigue in the LBP group highlight the complex and multi-factorial nature of LBP related to lifting. The feeling of fatigue was positively associated with pain ramp in the LBP group, suggesting a close relationship with pain and fatigue during lifting that requires further exploration.

An exploratory identification of biological markers of chronic musculoskeletal pain in the low back, neck, and shoulders

Objectives

This study was an in-depth exploration of unique data from a nationally representative sample of adults living in the United States to identify biomarkers associated with musculoskeletal pain.

Methods

We performed secondary analyses of 2003–2004 NHANES data. After a first screening of 187 markers, analyses of 31 biomarkers were conducted on participants aged ≥20 years identified in all counties using the 2000 Census Bureau data (n = 4,742). To assess the association of each biomarker with each pain outcome (acute, subacute and chronic low back, neck, and shoulder pain), analyses were carried out using multivariable logistic regression with adjustments for sex, age and body mass index. Biomarkers were considered as continuous variables and categorized at the median of their distributions.

Results

Pain at any site for ≥24 hours during the past month was reported by 1,214 participants. Of these, 779 mentioned that the pain had lasted for ≥3 months (“chronic pain”). α-carotene, ascorbic acid, β-carotene, mercury and total protein had a statistically significant, inverse association with ≥2 chronic pain sites. Acrylamide, alkaline phosphatase, cadmium, cotinine, glycidamide, homocysteine, retinol, triglycerides and white blood cell count were positively associated with ≥2 chronic pain sites. Few biological markers were associated with acute and subacute pain.

Conclusions

This study identified some biomarkers that were strongly and consistently associated with musculoskeletal pain. These results raise new hypotheses and could have tremendous implications for advancing knowledge in the field. Research on musculoskeletal pain needs to put more effort on the biological dimension of the biopsychosocial model of pain.

Multiple Factors Affecting Health-Related Quality of Life in Women With Chronic Multisite Musculoskeletal Pain: A Cross-Sectional Study in Ankara, Turkey

Although chronic multi-site musculoskeletal pain is known to cause decreased physical function and impair work and social life, there is insufficient research about its impact on health-related quality of life (HRQoL) in women. The aim of this study was to investigate multiple factors affecting HRQoL in women with chronic multi-site musculoskeletal pain. This study included 227 women with two or more musculoskeletal areas which were painful during the last 3 months. The HRQoL and musculoskeletal system symptoms were evaluated with the Nottingham Health Profile (NHP) and the Nordic Musculoskeletal Questionnaire (NMQ), respectively. Physical activity level, social functionality and depressive symptoms were assessed with the International Physical Activity Questionnaire-Short Form (IPAQ- SF), Social Functioning Scale (SFS) and Beck Depression Inventory (BDI), respectively. Significant predictors for the total score on the NHP were found to be the number of children (p < 0.001), social engagement/withdrawal scale (p:0.094), the number of regions with musculoskeletal pain during the last year (p:0.002) and last 7 days (p:0.036), depressive symptoms (p < 0.001), current employment status (p:0.084), and the presence of chronic disease (p < 0.001). The results of this study demonstrated that both sociodemographic characteristics, and social and psychological factors may affect the HRQoL in women with chronic multi-site musculoskeletal pain.

Distribution and prevalence of musculoskeletal pain co-occurring with persistent low back pain: a systematic review

BACKGROUND

Co-occurring musculoskeletal pain is common among people with persistent low back pain (LBP) and associated with more negative consequences than LBP alone. The distribution and prevalence of musculoskeletal pain co-occurring with persistent LBP has not been systematically described, which hence was the aim of this review.

METHODS

Literature searches were performed in MEDLINE, Embase, CINAHL and Scopus. We considered observational studies from clinical settings or based on cohorts of the general or working populations involving adults 18 years or older with persistent LBP (≥4 wks) and co-occurring musculoskeletal pain for eligibility. Study selection, data extraction and risk of bias assessment were carried out by independent reviewers. Results are presented according to study population, distribution and location(s) of co-occurring pain.

RESULTS

Nineteen studies out of 5744 unique records met the inclusion criteria. Studies were from high-income countries in Europe, USA and Japan. A total of 34,492 people with persistent LBP were included in our evidence synthesis. Methods for assessing and categorizing co-occurring pain varied considerably between studies, but based on the available data from observational studies, we identified three main categories of co-occurring pain - these were axial pain (18 to 58%), extremity pain (6 to 50%), and multi-site musculoskeletal pain (10 to 89%). Persistent LBP with co-occurring pain was reported more often by females than males, and co-occurring pain was reported more often in patients with more disability.

CONCLUSIONS

People with persistent LBP often report co-occurring neck pain, extremity pain or multi-site pain. Assessment of co-occurring pain alongside persistent LBP vary considerable between studies and there is a need for harmonisation of measurement methods to advance our understanding of how pain in different body regions occur alongside persistent LBP.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42017068807 .

Multi-site Pain Is Associated with Long-term Patient-Reported Outcomes in Older Adults with Persistent Back Pain

OBJECTIVE

To estimate the prevalence of co-occurring pain sites among older adults with persistent back pain and associations of multisite pain with longitudinal outcomes.

DESIGN

Secondary analysis of a cohort study.

SETTING

Three integrated health systems in the United States.

SUBJECTS

Eight hundred ninety-nine older adults with persistent back pain.

METHODS

Participants reported pain in the following sites: stomach, arms/legs/joints, headaches, neck, pelvis/groin, and widespread pain. Over 18 months, we measured back-related disability (Roland Morris, scored 0-24), pain intensity (11-point numerical rating scale), health-related quality of life (EuroQol-5D [EQ-5D], utility from 0-1), and falls in the past three weeks. We used mixed-effects models to test the association of number and type of pain sites with each outcome.

RESULTS

Nearly all (N = 839, 93%) respondents reported at least one additional pain site. There were 216 (24%) with one additional site and 623 (69%) with multiple additional sites. The most prevalent comorbid pain site was the arms/legs/joints (N = 801, 89.1%). Adjusted mixed-effects models showed that for every additional pain site, RMDQ worsened by 0.65 points (95% confidence interval [CI] = 0.43 to 0.86), back pain intensity increased by 0.14 points (95% CI = 0.07 to 0.22), EQ-5D worsened by 0.012 points (95% CI = -0.018 to -0.006), and the odds of falling increased by 27% (odds ratio = 1.27, 95% CI = 1.12 to 1.43). Some specific pain sites (extremity pain, widespread pain, and pelvis/groin pain) were associated with greater long-term disability.

CONCLUSIONS

Multisite pain is common among older adults with persistent back pain. Number of pain sites was associated with all outcomes; individual pain sites were less consistently associated with outcomes.

Effect of Comorbid Chronic Low Back Pain on Patient-Reported Outcome and Gait Parameters in Patients With Symptomatic Knee Osteoarthritis

Knee osteoarthritis and chronic low back pain are common and often coexist. There are limited studies on the impact of coexisting musculoskeletal disorders on gait parameters and its association with self-assessed functional outcome. This study compared gait parameters, self-assessed functional outcome measurements, and quality-of-life scales between patients with knee osteoarthritis against those with coexisting knee osteoarthritis and chronic low back pain using gait analysis, Western Ontario and McMaster Osteoarthritis Index, and Short Form-36. Three hundred sixty-seven patients underwent gait analysis after the question-based functional outcome measurement. Pain, function, and quality of life were worse in the coexisting knee osteoarthritis and chronic low back pain group (n = 197) compared with the knee osteoarthritis only group (n = 170, P = 0.017, P = 0.004, P < 0.001, P = 0.004, respectively). The coexisting knee osteoarthritis and chronic low back pain group had significantly lower gait velocity and cadence than the knee osteoarthritis group (P = 0.028 and P = 0.003). The Western Ontario and McMaster Osteoarthritis Index Pain subscore was associated with gait velocity (P < 0.001) in the knee osteoarthritis group, whereas Short Form-36 physical composite was associated with gait velocity (P < 0.001) in the coexisting knee osteoarthritis and chronic low back pain group. Comorbid chronic low back pain in patients with knee osteoarthritis was associated with worse pain, function, quality of life, gait velocity, and cadence. Compared with the Western Ontario and McMaster Osteoarthritis Index, Short Form-36 may be a more suitable tool to track mobility outcome measure, such as gait velocity, in the management of the coexisting knee osteoarthritis and chronic low back pain.

Associations of sickness absence for pain in the low back, neck and shoulders with wider propensity to pain

Objectives

To explore the association of sickness absence ascribed to pain at specific anatomical sites with wider propensity to musculoskeletal pain.

Methods

As part of the CUPID (Cultural and Psychosocial Influences on Disability) study, potential risk factors for sickness absence from musculoskeletal pain were determined for 11 922 participants from 45 occupational groups in 18 countries. After approximately 14 months, 9119 (78%) provided follow-up information about sickness in the past month because of musculoskeletal pain, including 8610 who were still in the same job. Associations with absence for pain at specific anatomical sites were assessed by logistic regression and summarised by ORs with 95% CIs.

Results

861 participants (10%) reported absence from work because of musculoskeletal pain during the month before follow-up. After allowance for potential confounders, risk of absence ascribed entirely to low back pain (n=235) increased with the number of anatomical sites other than low back that had been reported as painful in the year before baseline (ORs 1.6 to 1.7 for ≥4 vs 0 painful sites). Similarly, associations with wider propensity to pain were observed for absence attributed entirely to pain in the neck (ORs up to 2.0) and shoulders (ORs up to 3.4).

Conclusions

Sickness absence for pain at specific anatomical sites is importantly associated with wider propensity to pain, the determinants of which extend beyond established risk factors such as somatising tendency and low mood. Better understanding of why some individuals are generally more prone to musculoskeletal pain might point to useful opportunities for prevention.

Aging Back Clinics-a Geriatric Syndrome Approach to Treating Chronic Low Back Pain in Older Adults: Results of a Preliminary Randomized Controlled Trial

OBJECTIVE

Treating chronic low back pain (CLBP) with spine-focused interventions is common, potentially dangerous, and often ineffective. This preliminary trial tests the feasibility and efficacy of caring for CLBP in older adults as a geriatric syndrome in Aging Back Clinics (ABC).

DESIGN

Randomized controlled trial.

SETTING

Outpatient clinics of two VA Medical Centers.

SUBJECTS

Fifty-five English-speaking veterans aged 60-89 with CLBP and no red flags for serious underlying illness, prior back surgery, dementia, impaired communication, or uncontrolled psychiatric illness.

METHODS

Participants were randomized to ABC care or usual care (UC) and followed for six months. ABC care included 1) a structured history and physical examination to identify pain contributors, 2) structured participant education, 3) collaborative decision-making, and 4) care guided by condition-specific algorithms. Primary outcomes were low back pain severity (0-10 current and seven-day average/worst pain) and pain-related disability (Roland Morris). Secondary outcomes included the SF-12 and health care utilization.

RESULTS

ABC participants experienced significantly greater reduction in seven-day average (-1.22 points, P = 0.023) and worst pain (-1.70 points, P = 0.003) and SF-12 interference with social activities (50.0 vs 11.5%, P = 0.0030) at six months. ABC participants were less likely to take muscle relaxants (16.7 vs 42.3%, P = 0.0481). Descriptively, UC participants were more likely to experience pain-related emergency room visits (45.8% vs 30.8%) and to be exposed to non-COX2 nonsteroidal anti-inflammatory drugs (73.1% vs 54.2%).

CONCLUSIONS

These preliminary data suggest that ABC care for older veterans with CLBP is feasible and may reduce pain and exposure to other potential morbidity.

The Reliability and Concurrent Validity of PainMAP Software for Automated Quantification of Pain Drawings on Body Charts of Patients With Low Back Pain

BACKGROUND

The assessment of painful areas through printed body charts is a simple way for clinicians to identify patients with widespread pain in primary care. However, there is a lack in the literature about a simple and automated method designed to analyze pain drawings in body charts in clinical practice.

PURPOSE

To test the inter- and intra-rater reliabilities and concurrent validity of software (PainMAP) for quantification of pain drawings in patients with low back pain.

METHODS

Thirty-eight participants (16 [42.10%] female; mean age 50.24 [11.54] years; mean body mass index 27.90 [5.42] kg/m² ; duration of pain of 94.35 [96.11] months) with a current episode of low back pain were recruited from a pool of physiotherapy outpatients. Participants were instructed to shade all their painful areas on a body chart using a red pen. The body charts were digitized by separate raters using smartphone cameras and twice for one rater to analyze the intra-rater reliability. Both the number of pain sites and the pain area were calculated using ImageJ software (reference method). The PainMAP software used image processing methods to automatically quantify the data from the same digitized body charts.

RESULTS

The reliability analyses revealed that PainMAP has excellent inter- and intra-rater reliabilities to quantify the number of pain sites (intraclass correlation coefficient [ICC]_2,1 : 0.998 [95% confidence interval (CI) 0.996 to 0.999]; ICC_2,1 : 0.995 [95% CI 0.991 to 0.998]) and the pain area [ICC_2,1 : 0.998 (95% CI 0.995 to 0.999); ICC_2,1 : 0.975 (95% CI 0.951 to 0.987)], respectively. The standard error of the measurement was 0.22 (4%) for the number of pain sites and 0.03 cm² (4%) for the pain area. The Bland-Altman analyses revealed no substantive differences between the 2 methods for the pain area (mean difference = 0.007 [95% CI -0.053 to 0.067]).

CONCLUSION

PainMAP software is reliable and valid for quantification of the number of pain sites and the pain area in patients with low back pain.

Evaluation of a Cost-Effective Novel Diagnostic Method for Lumbar Herniated Disc with Knee-Osteoarthritis: A Randomized Sample Study

The aim of this study was to determine a cost-effective diagnostic method for lumbar herniated disc with knee osteoarthritis (LHD-KOA) based on aberrant outcome measures, levels of biomarkers, and examination of the lower-extremity. Data were separately analyzed for each cohort suffering with LHD-KOA (n=108; 59.82±7.15years) and without LHD-KOA (n=108; 58.81±7.61years), and findings were confirmed with radiological images. The aberrant-leg-features (bilateral: knee gaps between the short head of biceps femoris and the surface of the bed, diameters of calves and thighs, angles of straight leg raising, knee-flexion and -extension in a supine position) and biochemical parameters (Interleukin-10, Tumor necrosis factor-alpha, C-reactive protein, creatine kinase-muscle, and Aldolase-A), and outcome measures, Western Ontario and McMaster Universities osteoarthritis index (WOMAC), knee-injury osteoarthritis outcomes scale (KOOS), Oswestry disability index (ODI), and body mass index (BMI)for participants with and without LHD-KOA were evaluated with appropriate techniques. All the subjects underwent standardized physical examination and completed a questionnaire. The risk ratios and mean± standard deviations of biomarkers, anatomical features, and outcome measures of the experimental subjects were highly significant compared to controls (p<0.0001). Results suggest that monitoring the studied aberrant outcome measures, biomarkers, and lower-anatomical features may be a cost-effective diagnostic tool for LHD-KOA. Further research is recommended for an alternative treatment protocol for LHD-KOA.

Multisite joint pain in older Australian women is associated with poorer psychosocial health and greater medication use

Background

Musculoskeletal pain frequently occurs in more than one body region, with up to 80% of adults reporting more than one joint pain site in the last 12 months. Older people and females are known to be more susceptible to multiple joint pain sites, however the association of multisite joint pain with physical and psychosocial functions in this population are unknown.

Methods

Cross-sectional data from 579 women were analyzed. Women were asked "Which of your joints have been troublesome on most days of the past month?" Pain qualities were measured using the McGill Pain Questionnaire (Short Form) and PainDETECT, and health was assessed using the SF-36 and sociodemographic variables. Statistical analysis using generalized ordinal logistic regression included comparison of three joint pain groups: no joint pain, 1-4 sites of joint pain and ≥ 5 sites of joint pain.

Results

Two thirds of respondents had multisite pain (>1 site), and one third had ≥5 joint pain sites. Compared to women with fewer joint pain sites, women with >5 joint pain sites (multisite joint pain) had significantly poorer physical and emotional health-related quality of life, more severe pain, a higher probability of neuropathic pain, and a longer duration of pain. More than half of women in the multisite joint pain group were still employed, statistically significantly more than women with no joint pain. In the final model, pain duration, the number of medications, pain intensity (discomforting and distressing) and the physical component of health-related quality of life were significantly associated with increased number of joint pain sites.

Conclusions

Over one-third of older women in our sample had >5 painful joints in the last month. These women demonstrated significantly poorer psychosocial health, and increased medication use, than women with no or fewer sites of joint pain. Many women with multisite joint pain were still in the workforce, even when nearing retirement age. This study has important implications for future research into musculoskeletal pain, particularly in regards to womens health and wellbeing, and for clinical practice where there should be increased awareness of the implications of concurrent, multisite joint pain.

Characterizing chronic pain in late adolescence and early adulthood: prescription opioids, marijuana use, obesity, and predictors for greater pain interference

Introduction:

Chronic pain in late adolescence and young adults is understudied and poorly characterized.

Objectives:

We sought to characterize key variables that may impact pain interference in late adolescents and young adults with chronic pain, including prescription opioid use, marijuana use, psychological symptoms, and obesity.

Methods:

Retrospective, cross-sectional medical chart review for patients aged 17 to 23 years (N = 283; 61% Females) seeking care at a tertiary care pain clinic. Data on pain characteristics, health behaviors, and mental health distress were examined, in addition to self-reported pain intensity and interference.

Results:

Overlapping pain conditions were common in this young adult sample (mean ≥ 2 pain conditions). Back pain was the most commonly cited pain condition, and the majority of pain was of unknown etiology. Results revealed high rates for current opioid prescription, overweight or obese status, and mental health problems. Those using prescription opioids were more likely to endorse tobacco use and had greater pain interference. Importantly, the presence of mental health distress and opioid use were predictive of higher levels of pain-related interference.

Conclusion:

Treatment-seeking adolescents and young adults with chronic pain evidence complex care needs that include pain and mental comorbidities, as well as risky health behaviors. Pain and mental health distress were associated with poorer physical health, opioid prescription and marijuana use, and pain-related interference. Findings underscore the need for additional research on pain, treatment patterns, and health behaviors and their impact on developmental trajectories, as well as the need to develop and apply effective early interventions in this at-risk population.

Sleep problems and fatigue as predictors for the onset of chronic widespread pain over a 5- and 18-year perspective

BACKGROUND

Previous research suggests that sleep problems may be an important predictor for chronic widespread pain (CWP). With this study we investigated both sleep problems and fatigue as predictors for the onset of CWP over a 5-year and an 18-year perspective in a population free from CWP at baseline.

METHODS

To get a more stable classification of CWP, we used a wash-out period, including only individuals who had not reported CWP at baseline (1998) and three years prior baseline (1995). In all, data from 1249 individuals entered the analyses for the 5-year follow-up and 791 entered for the 18-year follow-up. Difficulties initiating sleep, maintaining sleep, early morning awakening, non-restorative sleep and fatigue were investigated as predictors separately and simultaneously in binary logistic regression analyses.

RESULTS

The results showed that problems with initiating sleep, maintaining sleep, early awakening and non-restorative sleep predicted the onset of CWP over a 5-year (OR 1.85 to OR 2.27) and 18-year (OR 1.54 to OR 2.25) perspective irrespective of mental health (assessed by SF-36) at baseline. Also fatigue predicted the onset of CWP over the two-time perspectives (OR 3.70 and OR 2.36 respectively) when adjusting for mental health. Overall the effect of the sleep problems and fatigue on new onset CWP (over a 5-year perspective) was somewhat attenuated when adjusting for pain at baseline but remained significant for problems with early awakening, non-restorative sleep and fatigue. Problems with maintaining sleep predicted CWP 18 years later irrespective of mental health and number of pain regions (OR 1.72). Reporting simultaneous problems with all four aspects of sleep was associated with the onset of CWP over a five-year and 18-yearperspective, irrespective of age, gender, socio economy, mental health and pain at baseline. Sleep problems and fatigue predicted the onset of CWP five years later irrespective of each other.

CONCLUSION

Sleep problems and fatigue were both important predictors for the onset of CWP over a five-year perspective. Sleep problems was a stronger predictor in a longer time-perspective. The results highlight the importance of the assessment of sleep quality and fatigue in the clinic.

Interaction between low back pain and knee pain contributes to disability level in individuals with knee osteoarthritis: a cross-sectional study

OBJECTIVE

To test the hypothesis that the interaction between low back pain (LBP) and knee pain intensity contributes to the disability level of individuals with knee osteoarthritis (OA).

DESIGN

Community-dwelling participants with knee OA (Kellgren/Lawrence [K/L] grade ≥1) were enrolled. LBP and its severity were identified using questionnaires. Knee pain severity and disability level were evaluated using the Japanese Knee Osteoarthritis Measure (JKOM) subscale. Multiple linear regression analyses were performed to examine the effect of the LBP-knee pain interaction, an independent variable, on disability, a dependent variable.

RESULTS

A total of 260 participants (age, 48-88 years; 77.7% women) were included. Of them, 151 (58.1%) had LBP. The LBP-knee pain interaction was significantly associated with disability after the adjustment for covariates. A post-hoc subgroup analysis revealed that the relationship between knee pain intensity and disability level was higher in individuals with LBP (beta: 0.621 points; 95% confidence interval [CI]: 0.511 to 0.731 points) than in those without LBP (beta: 0.402 points; 95% CI: 0.316 to 0.487 points).

CONCLUSIONS

LBP interacts with knee pain intensity and contributes to disability level in individuals with knee OA. Coexisting LBP and knee pain had a stronger impact on disability level than LBP or knee pain alone. These findings highlight the potential deteriorative effects of the LBP-knee interaction on disability. Maximal treatment effects for disability might be achieved when LBP and knee pain are targeted simultaneously, rather than separately.

Drivers of international variation in prevalence of disabling low back pain: Findings from the Cultural and Psychosocial Influences on Disability study

Background

Wide international variation in the prevalence of disabling low back pain (LBP) among working populations is not explained by known risk factors. It would be useful to know whether the drivers of this variation are specific to the spine or factors that predispose to musculoskeletal pain more generally.

Methods

Baseline information about musculoskeletal pain and risk factors was elicited from 11 710 participants aged 20–59 years, who were sampled from 45 occupational groups in 18 countries. Wider propensity to pain was characterized by the number of anatomical sites outside the low back that had been painful in the 12 months before baseline (‘pain propensity index’). After a mean interval of 14 months, 9055 participants (77.3%) provided follow‐up data on disabling LBP in the past month. Baseline risk factors for disabling LBP at follow‐up were assessed by random intercept Poisson regression.

Results

After allowance for other known and suspected risk factors, pain propensity showed the strongest association with disabling LBP (prevalence rate ratios up to 2.6, 95% CI: 2.2–3.1; population attributable fraction 39.8%). Across the 45 occupational groups, the prevalence of disabling LBP varied sevenfold (much more than within‐country differences between nurses and office workers), and correlated with mean pain propensity index (r = 0.58).

Conclusions

Within our study, major international variation in the prevalence of disabling LBP appeared to be driven largely by factors predisposing to musculoskeletal pain at multiple anatomical sites rather than by risk factors specific to the spine.

Significance

Our findings indicate that differences in general propensity to musculoskeletal pain are a major driver of large international variation in the prevalence of disabling low back pain among people of working age.

Association between somatic symptom burden and health-related quality of life in people with chronic low back pain

Depression is a relevant risk factor for low back pain and is associated with the outcomes of low back pain. Depression also often overlaps with somatisation. As previous studies have suggested that somatisation or a higher somatic symptom burden has a role in the outcomes of low back pain, the aim of the present cross-sectional study was to examine whether somatic symptom burden was associated with health-related quality of life in individuals with chronic low back pain independent of depression. We analyzed internet survey data on physical and mental health in Japanese adults aged 20–64 years with chronic low back pain (n = 3,100). Health-related quality of life was assessed using the EuroQol five dimensions (EQ-5D) questionnaire. Somatic symptom burden and depression were assessed using the Somatic Symptom Scale-8 (SSS-8) and the Patient Health Questionnaire-2 (PHQ-2), respectively. SSS-8 score was categorized as no to minimal (0–3), low (4–7), medium (8–11), high (12–15), and very high (16–32). The association between SSS-8 and EQ-5D was examined using linear regression models, adjusting for depression and other covariates, including age, sex, BMI, smoking, marital status, education, exercise, employment, and the number of comorbid diseases. A higher somatic symptom burden was significantly associated with a lower health-related quality of life independent of depression and the number of comorbid diseases (regression coefficient = 0.040 for SSS-8 high vs. very high and 0.218 for non to minimal vs. very high, p trend <0.0001). In conclusion, somatic symptom burden might be important for the health-related quality of life of individuals with chronic low back pain.

The influence of multisite pain and psychological comorbidity on prognosis of chronic low back pain: longitudinal data from the Norwegian HUNT Study

OBJECTIVES

This study aimed to investigate the prospective influence of multisite pain, depression, anxiety, self-rated health and pain-related disability on recovery from chronic low back pain (LBP).

SETTING

The data is derived from the second (1995-1997) and third (2006-2008) wave of the Nord-Trøndelag Health Study (HUNT) in Norway.

PARTICIPANTS

The study population comprises 4484 women and 3039 men in the Norwegian HUNT Study who reported chronic LBP at baseline in 1995-1997.

PRIMARY OUTCOME MEASURES

The primary outcome was recovery from chronic LBP at the 11-year follow-up. Persons not reporting pain and/or stiffness for at least three consecutive months during the last year were defined as recovered. A Poisson regression model was used to estimate adjusted risk ratios (RRs) with 95% CIs.

RESULTS

At follow-up, 1822 (40.6%) women and 1578 (51.9%) men reported recovery from chronic LBP. The probability of recovery was inversely associated with number of pain sites (P-trend<0.001). Compared with reporting 2-3 pain sites, persons with only LBP had a slightly higher probability of recovery (RR 1.10, 95% CI 0.98 to 1.22 in women and RR 1.10, 95% CI 1.01 to 1.21 in men), whereas people reporting 6-9 pain sites had substantially lower probability of recovery (RR 0.58, 95% CI 0.52 to 0.63 in women and RR 0.70, 95% CI 0.63 to 0.79 in men). Poor/not so good self-rated general health, symptoms of anxiety and depression, and pain-related disability in work and leisure were all associated with reduced probability of recovery, but there was no statistical interaction between multisite pain and these comorbidities.

CONCLUSIONS

Increasing number of pain sites was inversely associated with recovery from chronic LBP. In addition, factors such as poor self-rated health, psychological symptoms and pain-related disability may further reduce the probability of recovery from chronic LBP.

Epidemiological Differences Between Localized and Nonlocalized Low Back Pain

STUDY DESIGN

A cross-sectional survey with a longitudinal follow-up.

OBJECTIVES

The aim of this study was to test the hypothesis that pain, which is localized to the low back, differs epidemiologically from that which occurs simultaneously or close in time to pain at other anatomical sites SUMMARY OF BACKGROUND DATA.: Low back pain (LBP) often occurs in combination with other regional pain, with which it shares similar psychological and psychosocial risk factors. However, few previous epidemiological studies of LBP have distinguished pain that is confined to the low back from that which occurs as part of a wider distribution of pain.

METHODS

We analyzed data from CUPID, a cohort study that used baseline and follow-up questionnaires to collect information about musculoskeletal pain, associated disability, and potential risk factors, in 47 occupational groups (office workers, nurses, and others) from 18 countries.

RESULTS

Among 12,197 subjects at baseline, 609 (4.9%) reported localized LBP in the past month, and 3820 (31.3%) nonlocalized LBP. Nonlocalized LBP was more frequently associated with sciatica in the past month (48.1% vs. 30.0% of cases), occurred on more days in the past month and past year, was more often disabling for everyday activities (64.1% vs. 47.3% of cases), and had more frequently led to medical consultation and sickness absence from work. It was also more often persistent when participants were followed up after a mean of 14 months (65.6% vs. 54.1% of cases). In adjusted Poisson regression analyses, nonlocalized LBP was differentially associated with risk factors, particularly female sex, older age, and somatizing tendency. There were also marked differences in the relative prevalence of localized and nonlocalized LBP by occupational group.

CONCLUSION

Future epidemiological studies should distinguish where possible between pain that is limited to the low back and LBP that occurs in association with pain at other anatomical locations.

LEVEL OF EVIDENCE

2.

Pain extent and function in youth with physical disabilities

Background

The aim of this study was to increase our understanding of the role that spatial qualities of pain (location and extent) play in functioning, among youths with disabilities and chronic pain.

Methods

One-hundred and fifteen youths (mean age 14.4 years; SD ±3.3 years) with physical disabilities and chronic pain were interviewed and were asked to provide information about pain locations and their average pain intensity in the past week, and to complete measures of pain interference, psychological function and disability. Most of the participants in this sample were males (56%), Caucasian (68%), and had a cerebral palsy (34%) or muscular dystrophy (25%) problem. Most participants did not report high levels of disability ( X¯=12.7, SD ±9.5, range 0–60) or global pain intensity ( X¯=3.2, SD ±2.4, range 0–10).

Results

Pain at more than one body site was experienced by 91% of participants. There were positive associations between pain extent with pain interference (r = 0.30) and disability (r = 0.30), and a negative association with psychological function (r = –0.38), over and above average pain intensity. Additionally, pain intensity in the back (as opposed to other locations) was associated with more pain interference (r = 0.29), whereas pain intensity in the shoulders was associated with less psychological function (r = –0.18), and pain intensity in the bottom or hips was associated with more disability (r = 0.29).

Conclusion

The findings support the need to take into account pain extent in the assessment and treatment of youths with physical disabilities and chronic pain, call our attention about the need to identify potential risk factors of pain extent, and develop and evaluate the benefits of treatments that could reduce pain extent and target pain at specific sites.

The concurrence of musculoskeletal pain and associated work-related factors: a cross sectional study

Background

Several recent studies have described the presence of musculoskeletal complaints, presenting evidence that multisite musculoskeletal pain (MP) is more often present than single-site musculoskeletal pain. However, less is known about determinants of this multimorbidity, particularly, concerning the role of occupational factors and, mainly, what determines single or multisite pain. This study described the associations between pain in different body sites and investigated related factors to MP in workers from Brazil.

Methods

A total of 1070 workers (228 women and 842 men), from urban cleaning services and from shoe manufacturers, participated in this cross sectional study (response 97 %). Interviewer-administered questionnaire included sociodemographic factors, physical and psychosocial work demands, leisure-time activities and musculoskeletal pain which was presence of pain in previous seven days, considering eight body sites and MP, the sum score of all painful sites, varying 0–8. A factor analysis was performed that captured the nine variables of physical exposure into two latent factors. Associations of pain between different body sites were assessed. Cox regression analyses, presenting the prevalence ratio (PR), showed the related factors to MP.

Results

In the previous seven days, 30 % of workers had MP. For all body sites, comorbidity ranged from 72 % to 91 %. Having pain in one body site is associated with pain in other site and the associations between proximal sites were stronger than between more distal sites. High exposure to manual material handling and awkward postures (PR = 1.5, 95 % CI 1.1–2.0), job strain (PR = 1.2, 95 % CI 1.0–1.6), and low social support (PR = 1.3, 95 % CI 1.0–1.7) and being woman (PR = 1.7, 95 % CI 1.3–2.3) were associated with MP. Risk factors for single–site pain and for subsequent musculoskeletal comorbidity were very similar, suggesting an additive effect of risk factors.

Conclusions

Most workers reported MP that was associated with several work-related factors. The findings support the idea that multisite pain is a continuum of single-site pain, maintained by exposure to several risk factors, rather than the result of a specific risk factor that initiates the multisite pain but not single-site pain. Workplace interventions are needed to decrease the number of pain sites, in order to improve the worker’s health.

Clinical and neuropsychiatric correlates of lumbar spinal surgery in older adults: results of a pilot study

AIM

To improve selection of older lumbar surgical candidates, we surveyed correlates of functioning and satisfaction with surgery.

MATERIALS & METHODS

Prospective sample at lumbar spine surgery clinic. Patients (n = 48) were evaluated before surgery and after 3 months. Dependent variables were functioning and surgical satisfaction.

RESULTS

Baseline variables associated with disability at 3 months included cognitive status and widespread pain. There was clinically significant improvement with moderate effects sizes for anxiety and depression at follow-up. Patients with at least a 30% improvement in disability had better physical health-related quality of life and were less likely to report widespread pain before surgery.

CONCLUSION

Although preliminary, two novel potential predictors of lumbar surgery outcome include diminished cognitive functioning and widespread pain. Further study of these variables on post-surgical functioning and satisfaction may improve patient selection.

Sleep as a predictive factor for the onset and resolution of multi-site pain: a 5-year prospective study

Background

Disturbed sleep and pain often co-exist and the relationship between the two conditions is complex and likely reciprocal. This 5-year prospective study examines whether disturbed sleep can predict the onset of multi-site pain, and whether non-disturbed sleep can predict the resolution of multi-site pain.

Methods

The cohort (n = 1599) was stratified by the number of self-reported pain sites: no pain, pain from 1–2 sites and multi-site pain (≥3 pain sites). Sleep was categorized by self-reported sleep disturbance: sleep A (best sleep), sleep B and sleep C (worst sleep). In the no-pain and pain-from-1–2 sites strata, the association between sleep (A, B and C) and multi-site pain 5 years later was analysed. Further, the prognostic value of sleep for the resolution of multi-site pain at follow-up was calculated for the stratum with multi-site pain at baseline. In the analyses, gender, age, body mass index, smoking, physical activity and work-related exposures were treated as potential confounders.

Results

For individuals with no pain at baseline, a significantly higher odds ratio for multi-site pain 5 years later was seen for the tertile reporting worst sleep [odds ratio (OR) 4.55; 95% confidence interval (CI) 1.28–16.12]. Non-disturbed (or less disturbed) sleep had a significant effect when predicting the resolution of multi-site pain (to no pain) (OR 3.96; 95% CI 1.69–9.31).

Conclusion

In conclusion, sleep could be relevant for predicting both the onset and the resolution of multi-site pain. It seems to be a significant factor to include in research on multi-site pain and when conducting or evaluating intervention programmes for pain.

Deconstructing chronic low back pain in the older adult--Step by step evidence and expert-based recommendations for evaluation and treatment part III: Fibromyalgia syndrome

OBJECTIVE

To present the third in a series of articles designed to deconstruct chronic low back pain (CLBP) in older adults. The series presents CLBP as a syndrome, a final common pathway for the expression of multiple contributors rather than a disease localized exclusively to the lumbosacral spine. Each article addresses one of 12 important contributors to pain and disability in older adults with CLBP. This article focuses on fibromyalgia syndrome (FMS).

METHODS

A modified Delphi approach was used to create the evaluation and treatment algorithm, the table discussing the rationale behind each of the algorithm components, and the stepped-care drug recommendations. The team involved in the creation of these materials consisted of a principal investigator, a 5-member content expert panel, and a 9-member primary care panel. The evaluation and treatment recommendations were based on availability of medications and other resources within the Veterans Health Administration (VHA) facilities. However, non-VHA panelists were also involved in the development of these materials, which can be applied to both VA and civilian settings. The illustrative clinical case was taken from the clinical practice of the principal investigator.

RESULTS

Following expert consultations and a review of the literature, we developed an evaluation and treatment algorithm with supporting materials to aid in the care of older adults with CLBP who have concomitant FMS. A case is presented that demonstrates the complexity of pain evaluation and management in older patients with CLBP and concomitant FMS.

CONCLUSIONS

Recognition of FMS as a common contributor to CLBP in older adults and initiating treatment targeting both FMS and CLBP may lead to improved outcomes in pain and disability.

Specific and number of comorbidities are associated with increased levels of temporomandibular pain intensity and duration

Background

Temporomandibular pain disorder (TMD) is a common pain condition in the face. People with TMD report multiple pain comorbidities. The presence of fibromyalgia and migraine in people with TMD is associated with an increase in TMD pain intensity and duration. However, data on the relationship between increasing number of pain comorbidities and TMD pain are rare. The aims of this study were: firstly to evaluate the extent to which increasing number of comorbidities is associated with increasing TMD pain intensity and duration; and secondly to evaluate the extent to which the presence of specific comorbidities is associated with increasing TMD pain intensity and duration.

Methods

The sample included 180 people seeking TMD treatment at Boston and Montreal clinics. TMD was diagnosed using the Research Diagnostic Criteria for TMD. A Numerical Pain Rating Scale assessed TMD pain intensity and participants provided their TMD pain duration in a study questionnaire. The comorbidities of migraine, chronic fatigue syndrome, irritable bowel syndrome, interstitial cystitis and restless leg syndrome were diagnosed by 5 validated diagnostic questionnaires. The associations were analyzed by linear regression, controlling for confounders.

Results

There was a positive association between the number of comorbidities present and TMD pain intensity (p < 0.01) and between the number of comorbidities present and TMD pain duration (p < 0.01). Also, the presence of migraine was positively associated with TMD pain intensity (p < 0.01) and the presence of chronic fatigue syndrome was positively associated with TMD pain intensity (p < 0.05) and with TMD pain duration (p < 0.01). When TMD patients were separated into groups, these associations did not change for the myofascial pain group, whereas in the non-myofascial pain group, the relationship between number of comorbidities and TMD pain duration was the only one still present.

Conclusion

This study shows that the number of comorbidities is positively associated with TMD pain duration and intensity. The presence of specific conditions, such as migraine and chronic fatigue syndrome, is associated with an increase in TMD intensity and duration.

Musculoskeletal disorders in Norway: prevalence of chronicity and use of primary and specialist health care services

BACKGROUND

Uncertainty exists with regards to the extent of prevalence and health care use for musculoskeletal disorders in Norway. The aim of this study was to estimate the prevalence of chronic musculoskeletal disorders and to estimate the prevalence of persons receiving primary and specialist health services for these disorders.

METHODS

We used three data-sources. First, four discrete years of the nationally representative cross-sectional Survey of Health and Living Conditions (SHLC) conducted in 2002, 2005, 2008 and 2012 by Statistics Norway. Second, we used the Norwegian Patient Registry (NPR) to estimate the proportion of the population who used specialist health services in 2012. Third, we used the national register dataset for reimbursement of primary care physicians, chiropractors and physiotherapists (KUHR) to estimate the proportion of the population attending primary care physicians, chiropractors or physiotherapists in 2012. Age- and sex-specific prevalence/utilization estimates for musculoskeletal disorders were calculated.

RESULTS

In 2012, 18% of men and 27% of women reported musculoskeletal disorders lasting for six months or more in the SHLC. Primary health care services reimbursed for musculoskeletal disorders were used by 37% of women and 30% of men. Of these 32% (women) and 26% (men) were physician contacts and between 5 and 9% physiotherapist or chiropractor or combined contact types. Corresponding numbers for specialist services were 5% in men and 7% in women, where the majority was out-patient consultations. Low back and neck pain were the most common diagnoses both in the general population and as reason for health care utilization. We found that musculoskeletal disorders increased with age, however our results showed no variation in prevalence of chronic disorders between 2002 and 2012.

CONCLUSION

Chronic musculoskeletal disorders were common in the general population, with higher prevalence among women compared to men, and increasing prevalence with age. Musculoskeletal disorders had considerable impact on the use of primary and specialist health services in Norway. The use of register data on health service utilization may be a useful source for monitoring population trends, and for estimating the burden in terms of health and health service use.

Prevalence of low back pain as the primary pain site and factors associated with low health-related quality of life in a large Japanese population: a pain-associated cross-sectional epidemiological survey

OBJECTIVES

This study aimed to estimate the prevalence, magnitude, and direction of the associations among disability, pain intensity, number of pain sites, and health-related quality of life (HRQoL) in patients reporting low back pain (LBP) as their primary pain.

METHODS

In January 2009, an Internet survey was performed for randomly selected adults aged 20-79 years who were registered as Internet research volunteers. Of 20 044 respondents, individuals with LBP as the primary pain were analyzed for associations among disability, number of pain sites, and HRQoL. Factors associated with low HRQoL were examined using multiple logistic regression modeling.

RESULTS

Of the 20 044 respondents, 25.2 % (n = 5060) reported LBP and 13.5 % (n = 2696) reported LBP as their primary pain. Among those with LBP as the primary pain, HRQoL decreased with increase in disability and number of pain sites. In multivariate analyses, disability [adjusted odds ratio (aOR), 2.93-4.58], number of pain sites (aOR, 1.42-6.12), pain intensity ≥7 (aOR, 1.88), and age ≥60 years (aOR, 1.55) were associated with low HRQoL.

CONCLUSIONS

Approximately 13.5 % of patients reported LBP as their primary pain. Disability with absence from social activity and ≥7 pain sites were strongly associated with low HRQoL.

Does the association between musculoskeletal pain and sickness absence due to musculoskeletal diagnoses depend on biomechanical working conditions?

AIM

To investigate single-site and multi-site musculoskeletal pain as predictors of future sickness absence due to musculoskeletal disorders (MSD) among blue-collar employees in food industry, and to study to what extent this relationship depends on physical loading at work.

METHODS

Survey responses of 901 employees on working conditions and musculoskeletal pain during the past week were linked to their future sickness absence records obtained from the personnel register of a food industry company. Negative binomial regression models were computed to determine associations of pain in one and in multi-site with the number of sickness absence days due to MSD during a four-year follow-up. Analyses were made in the whole cohort and stratified by the occurrence of repetitive movements and awkward postures (low/high).

RESULTS

Multi-site pain occurred among 59 % in the total cohort and predicted sickness absence with a rate ratio of 1.48 [95 % confidence interval (CI) 1.21-1.80], adjusted for age, gender, biomechanical and psychosocial working conditions, body mass index and physical exercise. Similar associations were seen in the sub-cohorts with a low occurrence of repetitive movements (RR 2.18, CI 1.69-2.80) and awkward postures (RR 1.78, CI 1.39-2.28), but not in the sub-cohorts with a high occurrence of these exposure. Single-site pain was not predictive of sickness absence.

CONCLUSIONS

A very high level of sickness absence in biomechanically strenuous work was found. Multi-site pain predicted sickness absence due to MSD among the employees with low exposure, but not among those with high exposure.

Does anterior trunk pain predict a different course of recovery in chronic low back pain?

Patient characteristics associated with the course and severity of low back pain (LBP) and disability have been the focus of extensive research, however, known characteristics do not explain much of the variance in outcomes. The relationship between anterior trunk pain (ATP) and LBP has not been explored, though mechanisms for visceral referred pain have been described. Study objectives were: (1) determine prevalence of ATP in chronic LBP patients, (2) determine whether ATP is associated with increased pain and disability in these patients, and (3) evaluate whether ATP predicts the course of pain and disability in these patients. In this study, spinal outpatient department patients mapped the distribution of their pain and patients describing pain in their chest, abdomen or groin were classified with ATP. Generalized estimating equations were performed to investigate the relationship between ATP and LBP outcomes. A total of 2974 patients were included and 19.6% of patients reported ATP. At all time points, there were significant differences in absolute pain intensity and disability in those with ATP compared with those without. The presence of ATP did not affect the clinical course of LBP outcomes. The results of this study suggest that patients who present with LBP and ATP have higher pain and disability levels than patients with localised LBP. Visceral referred pain mechanisms may help to explain some of this difference.

Differences between patients with chronic widespread pain and local chronic low back pain in primary care--a comparative cross-sectional analysis

Background

Chronic pain is a common reason for consultation in general practice. Current research distinguishes between chronic localized pain (CLP) and chronic widespread pain (CWP). The aim of this study was to identify differences between CWP and chronic low back pain (CLBP), a common type of CLP, in primary care settings.

Methods

Fifty-eight German general practitioners (GPs) consecutively recruited all eligible patients who consulted for chronic low back pain during a 5-month period. All patients received a questionnaire on sociodemographic data, pain characteristics, comorbidities, psychosomatic symptoms, and previous therapies.

Results

GPs recruited 647 eligible patients where of a quarter (n = 163, 25.2%) met the CWP criteria according to the American College of Rheumatology. CWP patients had significantly more comorbidities and psychosomatic symptoms, showed longer pain duration, and suffered predominantly from permanent pain instead of distinguishable pain attacks. CWP patients were more often females, are less working and reported a current pension application or a state-approved grade of disability more frequently. We found no other differences in demographic parameters such as age, nationality, marital status, number of persons in household, education, health insurance status, or in health care utilization data.

Conclusions

This project is the largest study performed to date which analyzes differences between CLBP and CWP in primary care settings. Our results showed that CWP is a frequent and particularly severe pain syndrome.

Trial registration

German Clinical Trial Register, DRKS00003123.

Total knee replacement in patients with concomitant back pain results in a worse functional outcome and a lower rate of satisfaction

This study assessed the effect of concomitant back pain on the Oxford knee score (OKS), Short-Form (SF)-12 and patient satisfaction after total knee replacement (TKR). It involved a prospectively compiled database of demographics and outcome scores for 2392 patients undergoing primary TKR, of whom 829 patients (35%) reported back pain. Compared with those patients without back pain, those with back pain were more likely to be female (odds ratio (OR) 1.5 (95% confidence interval (CI) 1.3 to 1.8)), have a greater level of comorbidity, a worse pre-operative OKS (2.3 points (95% CI 1.7 to 3.0)) and worse SF-12 physical (2.0 points (95% CI 1.4 to 2.6)) and mental (3.3 points (95% CI 2.3 to 4.3)) components.

One year post-operatively, those with back pain had significantly worse outcome scores than those without with a mean difference in the OKS of 5 points (95% CI 3.8 to 5.4), in the SF-12 physical component of 6 points (95% CI 5.4 to 7.1) and in the mental component of 4 points (95% CI 3.1 to 4.9). Patients with back pain were less likely to be satisfied (OR 0.62, 95% CI 0.5 to 0.78).

After adjusting for confounding variables, concomitant back pain was an independent predictor of a worse post-operative OKS, and of dissatisfaction. Clinicians should be aware that patients suffering concomitant back pain pre-operatively are at an increased risk of being dissatisfied post-operatively.

Cite this article: Bone Joint J 2013;95-B:1632–9.

Endoprosthesis and obesity

INTRODUCTION

Obesity represents a significant risk factor in the pathophysiology of degenerative changes in coxarthrosis.

OBJECTIVE

The study aims to investigate obesity as a risk factor in the examined sample comprising 136 patients who underwent hip endoprothesis implantation.

MATERIAL AND METHODS

The series comprised 136 patients with a hip endoprosthesis implanted, where the patients' BMI, amount of blood used, duration of surgery, number of assistants, and type of anaesthesia were observed. Wounds and late post-operative complications, infections, haemorrhage, vein thrombosis, endoprosthesis dislocations, length of inpatient stay, start of physical therapy and full weight-bearing were also observed. The observation period lasted six months on average.

DISCUSSION

In simple terms, the three greatest factors when implanting a hip endoprosthesis are as follows: properties of the endoprosthesis, the orthopaedic surgeon's skill and experience, and individual characteristics of the patient, i.e. age, sex, health condition, body weight, BMI, adequate physical therapy.

CONCLUSION

We believe that the implantation of a hip endoprosthesis should be postponed for patients with a BMI exceeding 29.99. Such patients should receive endocrine treatment, they should undergo a weight loss programme in order to reduce their body weight and in order to reduce their BMI to under 29.99.

High prevalence of daily and multi-site pain--a cross-sectional population-based study among 3000 Danish adolescents

Background

Daily pain and multi-site pain are both associated with reduction in work ability and health-related quality of life (HRQoL) among adults. However, no population-based studies have yet investigated the prevalence of daily and multi-site pain among adolescents and how these are associated with respondent characteristics. The purpose of this study was to investigate the prevalence of self-reported daily and multi-site pain among adolescents aged 12–19 years and associations of almost daily pain and multi-site pain with respondent characteristics (sex, age, body mass index, HRQoL and sports participation).

Methods

A population-based cross-sectional study was conducted among 4,007 adolescents aged 12–19 years in Denmark. Adolescents answered an online questionnaire during physical education lessons. The questionnaire contained a mannequin divided into 12 regions on which the respondents indicated their current pain sites and pain frequency (rarely, monthly, weekly, more than once per week, almost daily pain), characteristics, sports participation and HRQoL measured by the EuroQoL 5D. Multivariate regression was used to calculate the odds ratio for the association between almost daily pain, multi-site pain and respondent characteristics.

Results

The response rate was 73.7%. A total of 2,953 adolescents (62% females) answered the questionnaire. 33.3% reported multi-site pain (pain in >1 region) while 19.8% reported almost daily pain. 61% reported current pain in at least one region with knee and back pain being the most common sites. Female sex (OR: 1.35-1.44) and a high level of sports participation (OR: 1.51-2.09) were associated with increased odds of having almost daily pain and multi-site pain. Better EQ-5D score was associated with decreased odds of having almost daily pain or multi-site pain (OR: 0.92-0.94).

Conclusion

In this population-based cohort of school-attending Danish adolescents, nearly two out of three reported current pain and, on average, one out of three reported pain in more than one body region. Female sex, and high level of sports participation were associated with increased odds of having almost daily pain and multi-site pain. The study highlights an important health issue that calls for investigations to improve our understanding of adolescent pain and our capacity to prevent and treat this condition.

Experimental placebo analgesia changes resting-state alpha oscillations

The lack of clear understanding of the pathophysiology of chronic pain could explain why we currently have only a few effective treatments. Understanding how pain relief is realised during placebo analgesia could help develop improved treatments for chronic pain. Here, we tested whether experimental placebo analgesia was associated with altered resting-state cortical activity in the alpha frequency band of the electroencephalogram (EEG). Alpha oscillations have been shown to be influenced by top-down processes, which are thought to underpin the placebo response.

Seventy-three healthy volunteers, split into placebo or control groups, took part in a well-established experimental placebo procedure involving treatment with a sham analgesic cream. We recorded ongoing (resting) EEG activity before, during, and after the sham treatment.

We show that resting alpha activity is modified by placebo analgesia. Post-treatment, alpha activity increased significantly in the placebo group only (p < 0.001). Source analysis suggested that this alpha activity might have been generated in medial components of the pain network, including dorsal anterior cingulate cortex, medial prefrontal cortex, and left insula.

These changes are consistent with a cognitive state of pain expectancy, a key driver of the placebo analgesic response. The manipulation of alpha activity may therefore present an exciting avenue for the development of treatments that directly alter endogenous processes to better control pain.

Is it all about a pain in the back?

Multisite musculoskeletal pain is common among people suffering from low back pain. Although the mechanisms behind co-occurrence of multiple somatic symptoms and musculoskeletal pain are still unknown, patients with co-morbidities and co-occurring musculoskeletal symptoms tend to have worse functional status, a poorer prognosis and respond less favourably to treatment. Evidence also suggests that the more pain sites a patient reports, the more reduced their physical and mental function will be regardless of location of pain. At the same time, evidence suggests that strategies for diagnosis and treatment of low back pain and other musculoskeletal disorders such as neck pain and lower limb osteoarthritis are very similar. In this chapter, we discuss the prevalence, consequences, and implications of commonalities between low back pain, pain in other sites and co-occurring pain. In addition, we propose a conceptual framework for a common stepwise approach to the diagnosis and management of back and musculoskeletal pain.

Patterns of multisite pain and associations with risk factors

To explore definitions for multisite pain, and compare associations with risk factors for different patterns of musculoskeletal pain, we analysed cross-sectional data from the Cultural and Psychosocial Influences on Disability (CUPID) study. The study sample comprised 12,410 adults aged 20–59 years from 47 occupational groups in 18 countries. A standardised questionnaire was used to collect information about pain in the past month at each of 10 anatomical sites, and about potential risk factors. Associations with pain outcomes were assessed by Poisson regression, and characterised by prevalence rate ratios (PRRs). Extensive pain, affecting 6–10 anatomical sites, was reported much more frequently than would be expected if the occurrence of pain at each site were independent (674 participants vs 41.9 expected). In comparison with pain involving only 1–3 sites, it showed much stronger associations (relative to no pain) with risk factors such as female sex (PRR 1.6 vs 1.1), older age (PRR 2.6 vs 1.1), somatising tendency (PRR 4.6 vs 1.3), and exposure to multiple physically stressing occupational activities (PRR 5.0 vs 1.4). After adjustment for number of sites with pain, these risk factors showed no additional association with a distribution of pain that was widespread according to the frequently used American College of Rheumatology criteria. Our analysis supports the classification of pain at multiple anatomical sites simply by the number of sites affected, and suggests that extensive pain differs importantly in its associations with risk factors from pain that is limited to only a small number of anatomical sites.

Role of functional brain imaging in understanding rheumatic pain

Rheumatic pain and, in particular, rheumatoid arthritis, osteoarthritis and fibromyalgia, are common and debilitating chronic pain syndromes. Recently, human functional neuroimaging, for example EEG, fMRI, and PET has begun to reveal some of the crucial central nervous system mechanisms underlying these diseases. The purpose of this review is to summarise current knowledge on the brain mechanisms of rheumatic pain revealed by functional neuroimaging techniques. The evidence suggests that two mechanisms may be largely responsible for the clinical pain associated with these rheumatic diseases: abnormalities in the medial pain system and/or central nervous system sensitisation and inhibition. If we can understand how functioning of the central nociceptive system becomes altered, even in the absence of peripheral nociceptive input, by using functional neuroimaging techniques, in the future we may be able to develop improved, more effective treatments for patients with chronic rheumatic pain.

Prevalence of low back pain as the primary pain site and factors associated with low health-related quality of life in a large Japanese population: a pain-associated cross-sectional epidemiological survey

OBJECTIVES: This study aimed to estimate the prevalence, magnitude, and direction of the associations among disability, pain intensity, number of pain sites, and health-related quality of life (HRQoL) in patients reporting low back pain (LBP) as their primary pain. METHODS: In January 2009, an Internet survey was performed for randomly selected adults aged 20-79 years who were registered as Internet research volunteers. Of 20 044 respondents, individuals with LBP as the primary pain were analyzed for associations among disability, number of pain sites, and HRQoL. Factors associated with low HRQoL were examined using multiple logistic regression modeling. RESULTS: Of the 20 044 respondents, 25.2 % (n = 5060) reported LBP and 13.5 % (n = 2696) reported LBP as their primary pain. Among those with LBP as the primary pain, HRQoL decreased with increase in disability and number of pain sites. In multivariate analyses, disability [adjusted odds ratio (aOR), 2.93-4.58], number of pain sites (aOR, 1.42-6.12), pain intensity ≥7 (aOR, 1.88), and age ≥60 years (aOR, 1.55) were associated with low HRQoL. CONCLUSIONS: Approximately 13.5 % of patients reported LBP as their primary pain. Disability with absence from social activity and ≥7 pain sites were strongly associated with low HRQoL.

The need to address the burden of musculoskeletal conditions

Musculoskeletal conditions are common in men and women of all ages across all socio-demographic strata of society. They are the most common cause of severe long-term pain and physical disability and affect hundreds of millions of people around the world. They impact on all aspects of life through pain and by limiting activities of daily living typically by affecting dexterity and mobility. They affect one in four adults across Europe [1]. Musculoskeletal conditions have an enormous economic impact on society through both direct health expenditure related to treating the sequelae of the conditions and indirectly through loss of productivity. The prevalence of many of these conditions increases markedly with age, and many are affected by lifestyle factors, such as obesity and lack of physical activity. The burden of these conditions is therefore predicted to increase, in particular in developing countries. The impact on individuals and society of the major musculoskeletal conditions is reviewed and effective prevention, treatment and rehabilitation considered. The need to recognise musculoskeletal conditions as a global public health priority is discussed.