Back sprain in industry. The role of socioeconomic factors in chronicity

Expectations for Return to Work Predict Return to Work in Workers with Low Back Pain: An Individual Participant Data (IPD) Meta-Analysis

Purpose Low back pain is associated with disability and lost productivity due to inability of workers to return to work. Personal recovery expectation beliefs may be associated with return to work outcomes in those with low back pain at high risk for chronic disability. We aimed to (1) assess whether workers' expectations for return to work, following a low back pain episode, are associated with subsequent return to work; and (2) explore the relationships between return to work expectations and other prognostic factors in their association with work outcomes.Methods We conducted an Individual Participant Data (IPD) meta-analysis using data from five prospective cohort studies identified by a Cochrane prognostic factor review. A one-stage IPD meta-analysis approach was applied. Multi-level mixed effects models were used to determine the unadjusted and adjusted associations between expectations and return to work (logistic regression) and time to return to work (parametric survival models with Weibull distribution).Results The final dataset included 2302 participants. Positive expectations for return to work were associated with return to work at follow-up in both unadjusted (Odds Ratio (OR) 2.95; 95% Confidence Interval (CI) 2.21, 3.95) (n = 2071) and comprehensively adjusted (OR 2.01; 95% CI 1.46, 2.77) (n = 1109) models. Similar findings were identified for shorter length of time to return to work in both unadjusted (HR 2.40; 95% CI 2.09, 2.75) (n = 1156) and minimally adjusted (HR 2.43; 95% CI 2.12, 2.79) (n = 1154) models.Conclusions Results suggest workers with low expectations for return to work are at increased risk for long-term work disability.

COVID-19 Pandemic Increases the Impact of Low Back Pain: A Systematic Review and Metanalysis

In March 2019, the World Health Organization (WHO) recognized the COVID-19 pandemic as a global issue. To reduce the spread of this disease, health safety pathways were implemented worldwide. These extraordinary measures changed people's lifestyles, e.g., by being forced to isolate, and in many cases, to work remotely from home. Low back pain (LBP), the most common cause of disability worldwide, is often a symptom of COVID-19. Moreover, it is often associated with different lifestyle features (type of job, physical activity, body weight). Therefore, the purpose of this systematic review and meta-analysis was to estimate the effect of the COVID-19 lockdown on LBP intensity and prevalence compared with LBP rates before the pandemic. A systematic search was performed on Scopus, PubMed, and Cochrane Central. Overall, eight studies with 2365 patients were included in the analysis. We used the Joanna Briggs Institute (JBI) critical appraisal tool to evaluate the risk of bias: six studies (75%) were at moderate risk of bias and two studies (25%) were at low risk of bias. These studies showed an increase in both the prevalence and intensity of LBP during the COVID-19 lockdown.

Does Workers' Compensation Status Affect Outcomes after Lumbar Spine Surgery? A Systematic Review and Meta-Analysis

Low back pain (LBP) is currently the leading cause of disability worldwide and the most common reason for workers’ compensation (WC) claims. Studies have demonstrated that receiving WC is associated with a negative prognosis following treatment for a vast range of health conditions. However, the impact of WC on outcomes after spine surgery is still controversial. The aim of this meta-analysis was to systematically review the literature and analyze the impact of compensation status on outcomes after lumbar spine surgery. A systematic search was performed on Medline, Scopus, CINAHL, EMBASE and CENTRAL databases. The review included studies of patients undergoing lumbar spine surgery in which compensation status was reported. Methodological quality was assessed through ROBINS-I and quality of evidence was estimated using the GRADE rating. A total of 26 studies with a total of 2668 patients were included in the analysis. WC patients had higher post-operative pain and disability, as well as lower satisfaction after surgery when compared to those without WC. Furthermore, WC patients demonstrated to have a delayed return to work. According to our results, compensation status is associated with poor outcomes after lumbar spine surgery. Contextualizing post-operative outcomes in clinical and work-related domains helps understand the multifactorial nature of the phenomenon.

Prevalence of low back pain in different educational levels: a systematic review

Abstract Introduction: Non-specific low back pain (LBP) can be understood through the interaction of biopsychosocial factors such as education. Unfortunately, it remains unclear whether education can be considered an important risk and prognostic factor for the occurrence of LBP. Objective: To investigate the association between education and LBP. Methods: The following databases were searched: MEDLINE, EMBASE, Cochrane, AMED and PsyINFO. Results: Thirteen studies were included in the review. The Prevalence Critical Appraisal Instrument (PCAI) was used to assess risk of bias. Methodological quality scores ranged from 7 to 10 on a scale of 0-10. There was a 23% (95% CI, 13-37) prevalence of LBP (10,582 out of a total of 99,457 cases) in the general sample at the time of assessment. The meta-analysis of studies on the prevalence of LBP in people with low, medium or high educational level found the following results, respectively: 24% (95% CI, 12-43), 27% (95% CI, 9-56), and 18% (95% CI, 5-50). The meta-regression identified heterogeneity among the studies included in the review. This can be explained by educational differences (p < 0.05). Conclusion: Occurrence of LBP varies according to educational level. Individuals with higher educational levels are less often affected by LBP than individuals with medium or low educational levels.

Do expectancies of return to work and Job satisfaction predict actual return to work in workers with long lasting LBP?

Background

Musculoskeletal disorders including low back pain have major individual and socioeconomic consequences as it often leads to disability and long-term sick leave and exclusion from working life. Predictors of disability and return to work often differ, and the dominant knowledge is on predictors for prolonged sick leave and disability. Therefore it is also important to identify key predictors for return to work. The aim of the study was to assess if overall job satisfaction and expectancies of return to work predicts actual return to work after 12 months, among employees with long lasting low back pain, and to assess if there were gender differences in the predictors.

Methods

Data from the Cognitive interventions and nutritional supplements trial (CINS Trial) was used. Predictors for return to work were examined in 574 employees that had been on sick leave 2–10 months for low back pain, before entering the trial. Data were analysed with multiple logistic regression models stratified by gender, and adjusted for potential confounders.

Results

Regardless of gender high expectancies were a strong and significant predictor of return to work at 12 months, while high levels of job satisfaction were not a significant predictor. There were no differences in the levels of expectancies or overall job satisfaction between men and women. However, men had in general higher odds of returning to work compared with women.

Conclusions

Among individuals with long lasting low back pain high expectancies of returning to work were strongly associated with successful return to work. We do not know what factors influence individual expectancies of return to work. Screening expectancies and giving individuals with low expectancies interventions with a goal to change expectancies of return to work, such as CBT or self-management interventions, may contribute to increase actual return to work.

Trial registration

http://www.clinicaltrials.gov/, with registration number NCT00463970. The trial was registered at the 18th of April 2007.

First episode of acute low back pain - an exploratory cluster analysis approach for early detection of unfavorable recovery

PURPOSE

To identify recovery patterns in patients with a first episode of acute low back pain (LBP) and to define risk factors for unfavorable outcome.

METHODS

One hundred and eight patients (55 male, 53 female; mean age = 40.8, SD 14.2 years) rated pain (NRS) and disability [Oswestry Disability Index (ODI)] before the first treatment and 1 week, 1, 3, 6, and 12 months later. Hierarchical cluster analysis identified recovery patterns based on NRS data. Clusters were compared for age, NRS and ODI at baseline, pain reduction in the first week, gender, radicular signs and traumatic onset using one-way ANOVA (post hoc Bonferroni) and χ² tests.

RESULTS

The cluster analysis revealed four clusters: moderate baseline pain/fast recovery; high baseline pain/fast recovery; high baseline pain/persistent mild pain; high baseline pain/persistent high pain. These clusters differed in baseline NRS [F(3,104) = 39.61, p < 0.001], baseline ODI [F(3,104) = 12.17, p < 0.001], pain reduction in the first week [F(3,104) = 11.51, p < 0.001] and in radicular signs [χ²(3) = 9.20, p = 0.027].

CONCLUSIONS

These results suggest that an initial and regularly repeated assessment of pain intensity and functional disability is important. Initial pain intensity does not seem to be a prognostic factor per se, as it did not negatively affect recovery provided that it decreased early in treatment. Implications for Rehabilitation Prediction of outcome is particularly important in patients with a first episode of acute LBP as one third did not completely recover. Pain intensity and functional disability should be initially assessed and regularly repeated in the first phase of treatment. High initial pain intensity and disability combined with small pain reduction during the first week might predict unfavorable outcome and require adequate treatment.

Using Locus of Control to Predict the Return-to-Work Achievements of Back-Injured Occupational Rehabilitation Clients

It has been proposed that perceived control plays an important role in influencing health-related behaviour. This study examined the relationship between locus of control and the return-to-work achievements of a group of back-injured workers' compensation claimants. The obtained results supported the hypothesised relationships between both ‘internal’ and ‘powerful others’ locus of control, and the return-to-work criterion variables. It was concluded that use of rehabilitation-specific measures of locus of control (such as were employed in the present study) could guide the program planning efforts of rehabilitation personnel dealing with this client group.

Is Compensation Bad for your Back?

A series of studies has tested the hypothesis that individuals with chronic pain (especially low back pain) who are receiving compensation respond less satisfactorily to treatment and rehabilitation than those not receiving it, and that symptoms and disability are reinforced and maintained by financial reward. Some examples of evidence for such ‘compensation neurosis’ are reviewed. The impact of socio-economic status, employment and litigation need also to be taken into account. The best response to individuals with chronic pain who are receiving compensation may not be the obvious punitive one of lowering or ceasing benefits. Rather, a compensation system minimising litigation and emphasising co-ordinated rehabilitation is advocated. The author challenges a common clinical — and political — bias against the so-called ‘compensation patient’.

Prognostic factors for return to work after low-back disc herniation surgery

Return to work (RTW) is an important outcome following disc herniation surgery. The present study aimed at determining factors that may affect early RTW after disc herniation surgery. Data were collected from 603 patients who underwent disc herniation surgery in an educational hospital via phone interviews during a 4-year period (2005-2009). Delayed RTW and failed RTW were associated with female gender, lower educational levels, longer hospitalization periods, greater BMI, biological age exceeding 40 years, employment in manual labor, lack of encouragement by the physician to RTW, being in pain at the time of the phone interview, having negative expectations about the outcome of surgery preoperatively, and low job satisfaction (P < .05). Psychological and occupational factors have direct effects on RTW. Important factors include positive expectations about the outcome of surgery, encouragement by the physician to RTW, job characteristics, and job satisfaction. RTW can be accelerated by appropriate strategies and team work.

[Socioeconomic position and duration of disability benefit due to work-related musculoskeletal disorders]

This study estimated the effect of socioeconomic position on the duration of disability benefits due to musculoskeletal disorders affecting the neck and/or upper limbs. A cohort study including 563 insured workers from the city of Salvador, Bahia, Brazil, registered in the General Social Security System and who received temporary disability benefits due to musculoskeletal disorders affecting the neck and/or upper limbs, was performed in 2008 using data from the National Social Security Institute. The results show that among union member workers with high psychosocial demands at work, those with low socioeconomic status are almost twice as likely to receive benefit for a shorter period of time compared to those with a higher socioeconomic position (RR = 1.89; 95%CI: 1.25-2.87). These results reveal an inequitable situation or unnecessary use of insurance for workers with a higher socioeconomic position. Future research aimed at elucidating the differences in the use of benefits are needed so that social insurance system managers may take the appropriate steps to resolve this issue.

Fatores associados à duração dos benefícios por incapacidade: um estudo de coorte

OBJETIVO: Analisar fatores associados à duração dos benefícios por incapacidade por doenças musculoesqueléticas na região cervical e/ou em membros superiores relacionadas ao trabalho. MÉTODOS: Estudo de coorte ambispectivo com 563 trabalhadores segurados do Regime Geral da Previdência Social que receberam benefício por incapacidade temporária por doenças musculoesqueléticas da região cervical e membros superiores relacionadas ao trabalho em Salvador, BA, em 2008. Os dados provieram de um inquérito conduzido pela Auditoria Regional do Instituto Nacional do Seguro Social e de registros administrativos. Foram analisadas variáveis sociodemográficas, relacionadas ao trabalho, características do agravo e aspectos relacionados ao seguro social. Os fatores associados ao tempo até a cessação do benefício foram identificados com técnicas de análise de sobrevida. RESULTADOS: Posição socioeconômica baixa (RR = 1,29; IC95% 1,02;1,64), idade abaixo de 39 anos (RR = 1,23; IC95% 1,03;1,47), reposição de renda pelo Instituto Nacional do Seguro Social < 100% (RR = 1,24; IC95% 1,04;1,47) e expectativa alta de retorno ao trabalho (RR = 1,20; IC95% 1,00;1,44) são as categorias relacionadas com maior taxa de cessação do benefício e sua menor duração. CONCLUSÕES: Fatores não estritamente médicos, como posição socioeconômica, idade, expectativa relativa ao retorno ao trabalho e nível de reposição de renda pelo Instituto Nacional do Seguro Social parecem influenciar a duração do benefício. Essas hipóteses deverão ser testadas posteriormente com estudos confirmatórios para aprimorar o entendimento do processo de determinação da incapacidade para o trabalho.

Factors associated with depressive symptoms in patients with chronic low back pain

OBJECTIVE

To investigate depressive symptoms and their related factors in patients with chronic low back pain in Korea.

METHOD

A cross-sectional study using data from the fourth Korea National Health and Nutrition Examination Survey (KNHANES IV) 2009 was undertaken. The sample consisted of 1,426 participants with chronic low back pain. Multifactorial regression analysis was used to identify the association between depressive symptoms and socioeconomic demographics and other chronic diseases.

RESULTS

Among the 371 (26.0%) patients with depression, significant factors associated with depressive symptoms were female gender (odds ratio [OR], 2.691; 95% confidence interval [CI], 1.724-4.199), medical aid beneficiary (OR, 1.371; 95% CI, 1.039-1.810), a dependent group for activities of daily living (OR, 1.570; 95% CI, 1.180-2.087), 'not good' in the perceived health category (OR, 2.309; 95% CI, 1.730-3.081) and in a cancer group (OR, 1.803; 95% CI, 1.051-3.093).

CONCLUSION

This study provides the foundation for managing patients with chronic low back pain and depressive symptoms. Clinicians managing chronic low back pain should consider risk factors for depressive symptoms.

Females exhibit shorter paraspinal reflex latencies than males in response to sudden trunk flexion perturbations

BACKGROUND

Females have a higher risk of experiencing low back pain or injury than males. One possible reason for this might be altered reflexes since longer paraspinal reflex latencies exist in injured patients versus healthy controls. Gender differences have been reported in paraspinal reflex latency, yet findings are inconsistent. The goal here was to investigate gender differences in paraspinal reflex latency, avoiding and accounting for potentially gender-confounding experimental factors.

METHODS

Ten males and ten females underwent repeated trunk flexion perturbations. Paraspinal muscle activity and trunk kinematics were recorded to calculate reflex latency and maximum trunk flexion velocity. Two-way mixed model analyses of variance were used to determine the effects of gender on reflex latency and maximum trunk flexion velocity.

FINDINGS

Reflex latency was 18.7% shorter in females than in males (P=0.02) when exposed to identical trunk perturbations, and did not vary by impulse (P=0.38). However, maximum trunk flexion velocity was 35.3% faster in females than males (P=0.01) when exposed to identical trunk perturbations, and increased with impulse (P<0.01). While controlling for differences in maximum trunk flexion velocity, reflex latency was 16.4% shorter in females than males (P=0.04).

INTERPRETATION

The higher prevalence of low back pain and injury among females does not appear to result from slower paraspinal reflexes.

Estimated number of korean adults with back pain and population-based associated factors of back pain : data from the fourth Korea national health and nutrition examination survey

OBJECTIVE

We estimated the number of Korean adults with back pain and evaluated population-based associated factors of back pain from a representative sample data from the Fourth Korea National Health and Nutrition Examination Survey.

METHODS

The number of Korean adults who experienced back pain (experienced patients), those who experienced back pain lasting for three or more months during the past year (chronic patients), and those who were currently suffering from back pain (current patients) were estimated by analyzing the data from the fourth Korea National Health and Nutrition Examination Survey conducted in 2007 using surveyfreq procedure of the SAS statistical package. Population-based odds ratios for being experienced, chronic, and current patient according to demographic (age and gender), socioeconomic (education and occupation), and lifestyle factors (smoking, drinking, and exercise) were estimated using surveylogistic procedure.

RESULTS

It was estimated that there were 5,554,256 (proportion, 15.4%; 95% CI, 4,809,466 - 6,299,046) experienced patients, 2,060,829 (5.7%; 1,557,413-2,564,246) chronic patients, and 3,084,188 (8.5%; 2,600,197 - 3,568,179) current patients among 36,107,225 Korean adults aged 20-89 years in 2007. Each of explanatory variables was significantly associated with at least one of the response variables for back pain.

CONCLUSION

Based on our study results, further efforts to investigate epidemiology of back pain, to evaluate associated factors, and to improve treatment outcomes are needed.

Predictors of delayed return to work after back injury: A case-control analysis of union carpenters in Washington State

METHODS

Union administrative records identified 20,642 union carpenters who worked in Washington State from 1989 to 2003. The Department of Labor and Industries provided records of workers' compensation claims and associated medical care. Work-related back claims (n = 4,241) were identified by ANSI codes (back, trunk, or neck/back) or ICD-9 codes relevant to medical care consistent with a back injury. Cases (n = 738) were defined as back injury claims with >90 days of paid lost time; controls (n = 699) resulted in return to work within 30 days. Logistic regression models estimated odds ratios and 95% confidence intervals (OR, 95% CI) of delayed return to work (DRTW).

RESULTS

Thirty percent of case claims and 8% of control claims were identified by an ICD-9 code. DRTW after back injury was associated with being female (2.7, 95% CI: 1.3-5.5), age 30-44 (1.2, 95% CI: 0.9-1.7) and age over 45 (1.6, 95% CI: 1.1-2.3), four or more years union experience (1.4, 95% CI: 1.1-1.8), previous paid time loss back claim (1.8, 95% CI: 1.3-2.5), and >or=30-day delay to medical care (3.6, 95% CI: 2.1, 6.1). Evidence of more acute trauma was also associated with DRTW.

CONCLUSIONS

Use of ICD-9 codes identified claims with multiple injuries that would otherwise not be captured by ANSI codes alone. Though carpenters of younger age and inexperience were at increased risk for a paid lost time back injury claim, older carpenters and more experienced workers, once injured, were more likely to have DRTW as were those who experienced acute events.

Narrative slope as a predictor of work and other occupational participation

This study aims to determine the utility of the narrative slope in predicting the vocational/productive outcomes of participants. For 65 participants living in supportive facilities for adults with HIV/AIDS in the United States, narrative slopes, based on the Occupational Performance History Interview II, were constructed and classified as progressive, stable, or regressive. Information regarding participants' productive activities was collected at discharge from intervention programming, and at 3-month intervals, up to 9 months. Data were analyzed to examine the relationship between narrative slope and engagement in employment and other productive activity post-intervention. Demographic variables were also analyzed. None of the demographic factors significantly correlated to outcomes. It was found that a more positive narrative slope was predictive of a higher likelihood of being employed or engaged in other productive activity.

Frequency and interrelations of risk factors for chronic low back pain in a primary care setting

Introduction

Many risk factors have been identified for chronic low back pain (cLBP), but only one study evaluated their interrelations. We aimed to investigate the frequency of cLBP risk factors and their interrelations in patients consulting their general practitioners (GPs) for cLBP.

Methods

A cross-sectional, descriptive, national survey was performed. 3000 GPs randomly selected were asked to include at least one patient consulting for cLBP. Demographic, clinical characteristics and the presence of cLBP risk factors were recorded. The frequency of each cLBP risk factor was calculated and multiple correspondence analysis (MCA) was performed to study their interrelations.

Results

A total of 2068 GPs (68.9%) included at least 1 patient, for 4522 questionnaires analyzed. In the whole sample of patients, the 2 risk factors most commonly observed were history of recurrent LBP (72.1%) and initial limitation of activities of daily living (66.4%). For working patients, common professional risk factors were beliefs, that LBP was due to maintaining a specific posture at work (79.0%) and frequent heavy lifting at work (65.5%). On MCA, we identified 3 risk-factor dimensions (axes) for working and nonworking patients. The main dimension for working patients involved professional risk factors and among these factors, patients' job satisfaction and job recognition largely contribute to this dimension.

Discussion

Our results shed in light for the first time the interrelation and the respective contribution of several previously identified cLBP risk factors. They suggest that risk factors representing a “work-related” dimension are the most important cLBP risk factors in the working population.

Opioid therapy for nonspecific low back pain and the outcome of chronic work loss

Outcomes of opioid therapy for noncancer pain remain to be more fully explored. Loss of work is among these outcomes. Especially when work loss becomes "chronic" (persists >or=90 days), it has profound psycho-social repercussions that compound suffering of those already in pain. Furthermore, costs escalate as work loss persists. We thus explored associations between opioid therapy for back pain and chronic work loss. Data consisted of workers compensation claims for nonspecific low back pain. We used multivariate analyses to control for diverse covariates. Workers with no opioid prescriptions constituted the reference group. Findings included the following: compared with the (no opioid) reference group, odds of chronic work loss were six times greater for claimants with schedule II ("strong") opioids; compared with the reference group, odds of chronic work loss were 11-14 times greater for claimants with opioid prescriptions of any type during a period of >or=90 days; and three years after injury, costs of claimants with schedule II opioids averaged $19,453 higher than costs of claimants in the reference group. Our analysis was not designed to ascertain antecedent causes, or why chronic work loss occurred in the first place. Rather, we focused on an ensuing consequence of opioid therapy, i.e., the outcome of chronic work loss, which occurred far removed in time (>or=90 days) after the worker's recorded date of back injury. The strong associations observed suggest that for most workers opioid therapy did not arrest the cycle of work loss and pain.

Why do some patients keep hurting their back? Evidence of ongoing back muscle dysfunction during remission from recurrent back pain

Approximately thirty-four percent of people who experience acute low back pain (LBP) will have recurrent episodes. It remains unclear why some people experience recurrences and others do not, but one possible cause is a loss of normal control of the back muscles. We investigated whether the control of the short and long fibres of the deep back muscles was different in people with recurrent unilateral LBP from healthy participants. Recurrent unilateral LBP patients, who were symptom free during testing, and a group of healthy volunteers, participated. Intramuscular and surface electrodes recorded the electromyographic activity (EMG) of the short and long fibres of the lumbar multifidus and the shoulder muscle, deltoid, during a postural perturbation associated with a rapid arm movement. EMG onsets of the short and long fibres, relative to that of deltoid, were compared between groups, muscles, and sides. In association with a postural perturbation, short fibre EMG onset occurred later in participants with recurrent unilateral LBP than in healthy participants (p=0.022). The short fibres were active earlier than long fibres on both sides in the healthy participants (p<0.001) and on the non-painful side in the LBP group (p=0.045), but not on the previously painful side in the LBP group. Activity of deep back muscles is different in people with a recurrent unilateral LBP, despite the resolution of symptoms. Because deep back muscle activity is critical for normal spinal control, the current results provide the first evidence of a candidate mechanism for recurrent episodes.

What is different about workers' compensation patients? Socioeconomic predictors of baseline disability status among patients with lumbar radiculopathy

STUDY DESIGN

Combined analysis of 2 prospective clinical studies.

OBJECTIVE

To identify socioeconomic characteristics associated with workers' compensation in patients with an intervertebral disc herniation (IDH) or spinal stenosis (SpS).

SUMMARY OF BACKGROUND DATA

Few studies have compared socioeconomic differences between those receiving or not receiving workers' compensation with the same underlying clinical conditions.

METHODS

Patients were identified from the Spine Patient Outcomes Research Trial (SPORT) and the National Spine Network (NSN) practice-based outcomes study. Patients with IDH and SpS within NSN were identified satisfying SPORT eligibility criteria. Information on disability and work status at baseline evaluation was used to categorize patients into 3 groups: workers' compensation, other disability compensation, or work-eligible controls. Enrollment rates of patients with disability in a clinical efficacy trial (SPORT) and practice-based network (NSN) were compared. Independent socioeconomic predictors of baseline workers' compensation status were identified in multivariate logistic regression models controlling for clinical condition, study cohort, and initial treatment designation.

RESULTS

Among 3759 eligible patients (1480 in SPORT and 2279 in NSN), 564 (15%) were receiving workers' compensation, 317 (8%) were receiving other disability compensation, and 2878 (77%) were controls. Patients receiving workers' compensation were less common in SPORT than NSN (9.2% vs. 18.8%, P < 0.001), but patients receiving other disability compensation were similarly represented (8.9% vs. 7.7%, P = 0.19). In univariate analyses, many socioeconomic characteristics significantly differed according to baseline workers' compensation status. In multiple logistic regression analyses, gender, educational level, work characteristics, legal action, and expectations about ability to work without surgery were independently associated with receiving workers' compensation.

CONCLUSION

Clinical trials involving conditions commonly seen in patients with workers' compensation may need special efforts to ensure adequate representation. Socioeconomic characteristics markedly differed between patients receiving and not receiving workers' compensation. Identifying the independent effects of workers' compensation on outcomes will require controlling for these baseline characteristics and other clinical features associated with disability status.

Determinants of "return to work in good health" among workers with back pain who consult in primary care settings: a 2-year prospective study

Many factors have been linked to return to work after a back pain episode, but our understanding of this phenomenon is limited and cross-sectional dichotomous indices of return to work are not valid measures of this construct. To describe the course of "return to work in good health" (RWGH--a composite index of back pain outcome) among workers who consulted in primary care settings for back pain and identify its determinants, a 2-year prospective study was conducted. Subjects (n = 1,007, 68.4%) were workers who consulted in primary care settings of the Quebec City area for a nonspecific back pain. They completed five telephone interviews over 2 years (follow-up = 86%). Analyses linking baseline variables with 2-year outcome were conducted with polytomous logistic regression. The proportion of "success" in RWGH increased from 18% at 6 weeks to 57% at 2 years. In women, persistent pain, pain radiating to extremities, increasing job seniority, not having a unionized job, feeling that the physician did listen carefully and increasing fear-avoidance beliefs towards work and activity were determinants of "failure" in RWGH. In men, decreasing age, cigarette smoking, poor self-reported health status, pain in the thoracic area, previous back surgeries, a non-compensated injury, high pain levels, belief that job is below qualifications, likelihood of losing job, job status, satisfaction with health services and fear-avoidance beliefs towards work were all significant. RWGH among workers with back pain receives multiple influences, especially among men. In both genders, however, fear-avoidance beliefs about work are associated with failure and high self-efficacy is associated with success.

Risk factors for sick leave due to musculoskeletal disorders among self-employed Dutch farmers: a case-control study

BACKGROUND

In Dutch agriculture, musculoskeletal disorders are a main cause of sick leave. Among self-employed insured farmers, neck, shoulder, upper extremity, and back disorders accounted for 30% of the claims for sick leave of less than 1 year This case-control study set out to identify and quantify risk factors for sick leave due to musculoskeletal disorders among self-employed Dutch farmers.

METHODS

Sick leave, claimed at an insurance company from 1998 to 2001 for back (SL-BP, n = 198) or neck/shoulder/upper extremity trouble (SL-EXT, n = 89) was analyzed; the controls did not file any claim in this period (n = 816).

RESULTS

Multivariate analysis showed that risk factors for SL-BP were increased age (OR = 1.06 per year, CI = 1.04-1.09), body mass index (BMI) >27 (OR = 1.93, CI = 1.2-3.2), smoking (OR = 1.90, CI = 1.2-2.9), former pain (OR = 3.28, CI = 2.1-5.1), tractor driving >1,000 hr/year (OR = 2.44, CI = 1.0-6.4), and "high work pace and workload" (OR = 1.59, CI = 1.0-2.4). SL-EXT was associated with pig (OR = 3.63, CI = 1.4-9.7), mushroom (OR = 6.14, CI = 1.4-27.2), or dairy/pig farming (OR = 4.56, 1.1-19.5), while age (OR = 1.10, CI = 1.06-1.14), smoking (OR = 1.79, CI = 1.0-3.2), and former pain (OR = 3.37, CI = 1.9-6.1) were also contributing.

CONCLUSIONS

Prevention of sick leave of self-employed farmers should focus on life style (obesity, smoking), reducing older farmers' exposure to physical load, exposure to long-term tractor driving. Specific attention should be paid to animal and mushroom farmers.

Predicting return to work after low back injury using the Psychosocial Risk for Occupational Disability Instrument: a validation study

INTRODUCTION

This paper reports on the predictive validity of a Psychosocial Risk for Occupational Disability Scale in the workers' compensation environment using a paper and pencil version of a previously validated multimethod instrument on a new, subacute sample of workers with low back pain.

METHODS

A cohort longitudinal study design with a randomly selected cohort off work for 4-6 weeks was applied. The questionnaire was completed by 111 eligible workers at 4-6 weeks following injury. Return to work status data at three months was obtained from 100 workers. Sixty-four workers had returned to work (RTW) and 36 had not (NRTW).

RESULTS

Stepwise backward elimination resulted in a model with these predictors: Expectations of Recovery, SF-36 Vitality, SF-36 Mental Health, and Waddell Symptoms. The correct classification of RTW/NRTW was 79%, with sensitivity (NRTW) of 61% and specificity (RTW) of 89%. The area under the ROC curve was 84%.

CONCLUSIONS

New evidence for predictive validity for the Psychosocial Risk-for-Disability Instrument was provided.

IMPLICATIONS

The instrument can be useful and practical for prediction of return to work outcomes in the subacute stage after low back injury in the workers' compensation context.

A clinical return-to-work rule for patients with back pain

BACKGROUND

Tools for early identification of workers with back pain who are at high risk of adverse occupational outcome would help concentrate clinical attention on the patients who need it most, while helping reduce unnecessary interventions (and costs) among the others. This study was conducted to develop and validate clinical rules to predict the 2-year work disability status of people consulting for nonspecific back pain in primary care settings.

METHODS

This was a 2-year prospective cohort study conducted in 7 primary care settings in the Quebec City area. The study enrolled 1007 workers (participation, 68.4% of potential participants expected to be eligible) aged 18-64 years who consulted for nonspecific back pain associated with at least 1 day's absence from work. The majority (86%) completed 5 telephone interviews documenting a large array of variables. Clinical information was abstracted from the medical files. The outcome measure was "return to work in good health" at 2 years, a variable that combined patients' occupational status, functional limitations and recurrences of work absence. Predictive models of 2-year outcome were developed with a recursive partitioning approach on a 40% random sample of our study subjects, then validated on the rest.

RESULTS

The best predictive model included 7 baseline variables (patient's recovery expectations, radiating pain, previous back surgery, pain intensity, frequent change of position because of back pain, irritability and bad temper, and difficulty sleeping) and was particularly efficient at identifying patients with no adverse occupational outcome (negative predictive value 78%- 94%).

INTERPRETATION

A clinical prediction rule accurately identified a large proportion of workers with back pain consulting in a primary care setting who were at a low risk of an adverse occupational outcome.

Treatment duration and cost of work-related low back pain in Korea

The purpose of this study is to present the information on the duration of treatment and the cost of work-related low back pain. Using the compensation-database for 1997 work-related low back pain (n=9,277), this study estimated the duration of treatment, the cost of work-related low back pain, the relationship between them, and probability of being off treatment at different intervals. The mean and the median of the treatment duration are 252.6 days and 175 days. The mean and the median of the cost of total insurance benefit are 37,700,000 won and 14,400,000 won. The treatment duration of 51% of the study subjects was less than 6 months and their cost accounted for 10.2% of the total insurance benefit. The subjects who were treated more than 24 months were 5.8% but it accounted for 29.2% of the cost. It was found that approximately 50% of the subjects who will remain on treatment at the end of n months would be off treatment at the end of n+5 months. This study presents the point in time when the low back pain (LBP) workers need to prepare to return to work by forecasting their off-treatment period. From the treat duration and cost perspectives, this study may be utilized as evidence for active management of work-related LBP.

Ergonomic Pain--Part 2: Differential Diagnosis and Management Considerations

Work-related musculoskeletal disorders (MSDs) can produce ergonomic pain in several different regions of the body, including the shoulder, elbow, wrist and hand, lumbar spine, knee, and ankle/foot. Each family of disorders is distinctive in presentation and requires diagnosis-specific interventions. Because of the complex nature of these disorders, management approaches may not always eliminate symptoms and or completely restore patient function to a level found prior to symptom onset. As a consequence, ergonomic measures should be implemented to reduce the overload on tissue and contribute to patient recovery. However, functional limits may persist and the clinician must make further decisions regarding a person's functional status in the chronic stages of the patient's care.

Prediction of chronic disability in work-related musculoskeletal disorders: a prospective, population-based study

BACKGROUND

Disability associated with work-related musculoskeletal disorders is an increasingly serious societal problem. Although most injured workers return quickly to work, a substantial number do not. The costs of chronic disability to the injured worker, his or her family, employers, and society are enormous. A means of accurate early identification of injured workers at risk for chronic disability could enable these individuals to be targeted for early intervention to promote return to work and normal functioning. The purpose of this study is to develop statistical models that accurately predict chronic work disability from data obtained from administrative databases and worker interviews soon after a work injury. Based on these models, we will develop a brief instrument that could be administered in medical or workers' compensation settings to screen injured workers for chronic disability risk.

METHODS

This is a population-based, prospective study. The study population consists of workers who file claims for work-related back injuries or carpal tunnel syndrome (CTS) in Washington State. The Washington State Department of Labor and Industries claims database is reviewed weekly to identify workers with new claims for work-related back injuries and CTS, and these workers are telephoned and invited to participate. Workers who enroll complete a computer-assisted telephone interview at baseline and one year later. The baseline interview assesses sociodemographic, employment-related, biomedical/health care, legal, and psychosocial risk factors. The follow-up interview assesses pain, disability, and work status. The primary outcome is duration of work disability over the year after claim submission, as assessed by administrative data. Secondary outcomes include work disability status at one year, as assessed by both self-report and work disability compensation status (administrative records). A sample size of 1,800 workers with back injuries and 1,200 with CTS will provide adequate statistical power (0.96 for low back and 0.85 for CTS) to predict disability with an alpha of.05 (two-sided) and a hazard ratio of 1.2. Proportional hazards regression models will be constructed to determine the best combination of predictors of work disability duration at one year. Regression models will also be developed for the secondary outcomes.

Chronicité, récidive et reprise du travail dans la lombalgie : facteurs communs de pronostic

OBJECTIVE

To determine the common risk factors of recurrence, chronicity and non return to work in low back pain.

MATERIAL AND METHOD

A systematic review of the literature was done by searches of Medline, Embase, Pascal, the Cochrane database and also in the unindexed literature. Keywords used were low back pain, chronic, risk factors, recurrence, predictive value of tests, prognosis, confounding factors. Studies were assessed by two readers using the ANAES (French Agency for Health Assessment) scale allowing classification into high-, moderate- and low-quality trials. The scientific evidence level of the identified risk factors depend on the methodological quality of the studies, the number of studies in agreement, the coherence of their results and their clinical relevance.

RESULTS

Fifty-four high quality studies were included. Several prognostic factors are common to the three described clinical situations. A history of low back pain (including the concept of pain severity, duration, disability, leg pain, related sickness leave and a history of spinal surgery), low level of job satisfaction and poor general health are highlighted with a strong level of evidence. Socioprofessionel and psychological factors including employment status, amount of wage, workers' compensation, and depression were found but with moderate level of evidence. Physical factors including lifting time per day and work postures were also found with moderate level of evidence.

CONCLUSION

This study confirm that several prognostic factors are commun to recurrence, chronicity and non return to work in low back pain. Early identification of these factors is important in understanding, and hopefully preventing, the recurrence or the progression to chronicity and disability in low back trouble.

Methodologic issues in the use of workers' compensation databases for the study of work injuries with days away from work. I. Sensitivity of case ascertainment

BACKGROUND

Case ascertainment costs vary substantially between primary and secondary data sources. This review summarizes information on the sensitivity of state administrative databases in workers' compensation systems for the ascertainment of days-away-from-work (DAFW) work injuries for use in modeling studies.

METHODS

Review of the literature supplemented by data from governmental or organizational reports or produced for this report.

RESULTS

Employers currently appear to provide workers' compensation insurance coverage for 98.9% of wage and salary workers. Wage and salary jobs account for approximately 90% of jobs in the United States. In industries such as manufacturing, the fraction of covered jobs is probably closer to 98%. In Minnesota, the number of DAFW cases ascertained by the Bureau of Labor Statistics' annual survey of occupational injuries and illnesses is approximately 92-97% concordant with the number of wage compensation claims for injuries producing DAFW over the period 1992-2000, once adjustments are made to permit direct comparisons of the numbers. The workers' compensation databases provide information for more than 95% of the total DAFW resulting from work injuries. Covariate estimates are unaffected by this less than 5% loss because effects appear dependent on time from injury.

CONCLUSIONS

Statewide workers' compensation administrative databases can have substantial utility for epidemiologic study of work injuries with DAFW because of their size, using high sensitivity for case ascertainment as the evaluative criterion.

Familial disability patterns in individuals with chronic work-related spine injury/illness

STUDY DESIGN

A case control study of familial disability patterns and other potential risk factors identified in a group of individuals with work-related spine injury/illness.

OBJECTIVES

The objective of the present study is to provide information on the relationship between a disabled family member and work-related spine injuries or illnesses leading to disability among another family member.

SUMMARY OF BACKGROUND DATA

Extensive studies have been conducted to identify the medical and nonmedical factors associated with prolonged disability after work-related spine injury/illness. Many of the relevant nonmedical factors are psychosocial and are dependent to some degree on family of origin environment and experience. Although similar recurring pain behaviors have been described in certain families, no recent study has been conducted of coexisting family disabilities in individuals with work-related spine injury/illness.

METHODS

A case-control investigation examining nine potential risk factors, including familial disability patterns, for the development of disability following work-related spine injury/illness was conducted. The case group (n = 88) consisted of individuals disabled from any and all gainful employment, whereas the controlled group (n = 40) continued working in spite of their spine complaints.

RESULTS

In this study, gender, number of spinal areas involved, current injury considerations/severity, and having a primary family member or spouse similarly disabled were found to be significant predictors of disability following work-related spine injury/illness. However, further analysis revealed that having an associated family disability was the greatest predictor of disability in the study group.

CONCLUSIONS

These data suggest that the presence of a primary family member or spouse with a work-related spine disability may be a risk factor for the development of disability in individuals sustaining a work-related spine injury.

Looking back on back pain: trial and error of diagnoses in the 20th century

CONTEXT

The societal costs of low back pain and associated disability are immense. However, very little is known about the etiology of low back pain. Lumbar disc disease was discovered in the last century and became the predominant etiology for back pain. Today we know that for the majority of low back pain cases, a specific etiology cannot be determined.

OBJECTIVE

To analyze the evolution of the "disc paradigm" and to compare our contemporary understanding to the scientific discussion in the beginning of the last century.

DESIGN

Survey of the highest ranked German medical journal from 1900 to 1999.

DATA EXTRACTION

The indexes of 5185 journal issues of the Deutsche Medizinische Wochenschrift were reviewed for articles about low back pain.

DATA SYNTHESIS

For each article, the etiologies were identified, categorized, and counted per decade. In addition, each important etiology was described.

CONCLUSIONS

In the beginning of the last century, many heterogeneous etiologies coexisted. In the second half of the century, the theory of disc degeneration took over almost the entire literature about low back pain. Pre-existing theories disappeared, but re-entered the discussion in the last decade. Two factors seemed to influence this development: 1) a tendency to prefer organic, visible abnormalities as etiologies; and 2) an inclination to trust technical diagnostic results more than clinical judgment.

Early workplace intervention for employees with musculoskeletal-related absenteeism: a prospective controlled intervention study

Sickness absenteeism caused by musculoskeletal disorders (MSDs) is a persistent and costly occupational health challenge. In a prospective controlled trial, we compared the effects on sickness absenteeism of a more proactive role for insurance case managers as well as workplace ergonomic interventions with that of traditional case management. Patients with physician-diagnosed MSDs were randomized either to the intervention group or the reference group offered the traditional case management routines. Participants filled out a comprehensive questionnaire at the initiation of the study and after 6 months. In addition, administrative data were collected at 0.6, and 12 months after the initiation of the project. For the entire 12-month period, the total mean number of sick days for the intervention group was 144.9 (SEM 11.8) days/person as compared to 197.9 (14.0) days in the reference group (P < 0.01). Compared with the reference group, employees in the intervention group significantly more often received a complete rehabilitation investigation (84% versus 27%). The time for doing this was reduced by half (59.4 (5.2) days versus 126.8 (19.2), P < .01). The odds ratio for returning to work in the intervention group was 2.5 (95% confidence interval 1.2-5.1) as compared with the reference group. The direct cost savings were USD 1195 per case, yielding a direct benefit-to-cost ratio of 6.8. It is suggested that the management of MSDs should to a greater degree focus on early return to work and building on functional capacity and employee ability. Allowing the case managers a more active role as well as involving an ergonomist in workplace adaptation meetings might also be beneficial.

The effect of cigarette smoking on musculoskeletal-related disability

BACKGROUND

This study describes cigarette smoking's effect on development of physical disability following initial musculoskeletal-related hospitalization.

METHODS

We followed 15,140 US Army personnel hospitalized for common musculoskeletal disorders between 1989-1996 for up to 8 years (1997) to assess risk for long-term physical disability.

RESULTS

Trends between increased smoking level and long-term disability were identified for persons with knee injuries, rotator cuff injuries, and intervertebral disc displacement. In proportional hazards models, disability was significantly associated with heavy smoking among all subjects (relative hazard (RH) = 1.21). Both heavy smokers (RH = 1.49) and light to moderate smokers (RH = 1.44) were at greater risk for disability following meniscal injuries. Excess fraction due to smoking among subjects with meniscal injuries who currently smoke was 38%.

CONCLUSIONS

Findings suggest an association between smoking and development of disability following meniscal injury. Given the high excess fraction of disability associated with smoking, other studies are needed to confirm this association.

Psychometric properties of the Tampa Scale for kinesiophobia and the fear-avoidance beliefs questionnaire in acute low back pain

The transition from acute to chronic low back pain (LBP) is influenced by many interacting factors. Pain-related fear, as measured by the Tampa Scale for Kinesiophobia (TSK) and the Fear-Avoidance Beliefs Questionnaire (FABQ), is one of these factors. The objectives of this study were to investigate, in a population with acute LBP, the reliability of TSK and FABQ through evaluation of the internal consistency, the test-retest reliability, and the concurrent validity between TSK and FABQ. One hundred and Seventy-Six patients suffering LBP for no longer than 4 weeks completed a Visual Analogue Scale for pain (VAS), the TSK, the FABQ, and a socio-demographic questionnaire. Each patient completed the VAS, TSK, and FABQ twice within 24 h. Internal consistency of TSK and FABQ scores range from alpha=0.70 to 0.83. Test-retest reliability ranges from r(s)=0.64 to 0.80 (P<0.01). Concurrent validity is moderate, ranging from r(s) =0.33 to 0.59 (P<0.01). It may be concluded that in a population with acute LBP, both the TSK and the FABQ are reliable measures of pain-related fear. In the clinical setting they may provide the practitioner a means of identifying pain-related fear in a patient with acute LBP.

Are components of a comprehensive medical assessment predictive of work disability after an episode of occupational low back trouble?

STUDY DESIGN

One hundred fifty-nine subacute low back work-injured patients completed a full medical assessment at baseline. A full repeat examination was performed 3 months later, when return-to-work status was determined.

OBJECTIVE

To determine the prognostic value of a comprehensive medical assessment for the prediction of return-to-work status.

SUMMARY OF BACKGROUND DATA

A systematic review of the work disability prediction literature of low back trouble prognosis revealed that no high-quality studies included a full medical history and physical examination in the design. The results of studies included in the systematic review were equivocal with respect to predictive usefulness of medical variables.

METHODS

Participants completed medical history questionnaires and then were clinically examined by one of six experienced examiners (three physicians and three physiotherapists). Return-to-work status was measured 3 months later, and predictive validity was evaluated using logistic regression modeling.

RESULTS

Medical variables (, medical history subscales, physical examination subscales, and lumbar range-of-motion tests) showed modest correct classification rates varying between 61.6% and 69.1% for participants.

CONCLUSIONS

Comprehensive medical assessments play a crucial role in the early identification of serious pathology after low back trouble. We were unable to identify, however, any medical evaluation variables that would account for significant proportions of variance in return to work. The weight of evidence obtained in this study suggests that injured workers' subjective interpretations and appraisals may be more powerful predictors of the course of postinjury recovery than exclusively medical assessments.

Biopsychosocial multivariate predictive model of occupational low back disability

STUDY DESIGN

To establish outcome, 253 workers with subacute and chronic low back conditions were assessed with a comprehensive multimethod biopsychosocial protocol at baseline, 3 days after the initial examination, and 3 months later.

OBJECTIVE

To validate empirically a biopsychosocial model for prediction of occupational low back disability.

SUMMARY OF BACKGROUND DATA

Costs of low back occupational disability continue to spiral despite stabilization of low back injury rates. An empirically based model to predict occupational disability in workers with low back injuries is required.

METHODS

Workers with subacute low back injuries (4-6 weeks after injury, n = 192) and those with chronic back pain (6-12 months after injury, n = 61) were the study participants. The biopsychosocial protocol included five groups of variables: 1) sociodemographic, 2) medical, 3) psychosocial, 4) pain behavior, and 5) workplace-related factors. Predictive validity was investigated through a 3-month follow-up assessment, at which time the return to work outcome was determined. Stepwise logistic regression models were developed to predict work status.

RESULTS

The final integrated model consisted of variables from a wide biopsychosocial spectrum: vitality, health transition, feeling that job is threatened due to injury, expectations of recovery, guarding behavior, perception of severity of disability, time to complete walk, and right leg typical sciatica.

CONCLUSIONS

The "winning" variables identified in the integrated model are dominated by cognitions, which are accompanied by disability behaviors. A cognitive-behavioral model with an adaptation-oriented rather than a pathology-oriented focus is favored for early intervention with high-risk workers since cognitions are amenable to change.

Educational achievement and chronic pain disability: mediating role of pain-related cognitions

OBJECTIVE

This study examined the relation between level of educational achievement (LOE) and the clinical morbidity associated with chronic pain.

SETTING

a multidisciplinary pain rehabilitation program located within a university hospital.

PATIENTS

Two hundred ninety-nine consecutive patients with chronic spinal pain, average age 39.6 years (SD = 10.7) and with an average duration of pain of 41.9 months (SD = 51.6).

OUTCOME MEASURES

Age, duration of pain, sex, and compensation and litigation status were controlled for in the statistical analysis because each was found to be significantly associated with LOE. Pain intensity was assessed by the McGill Pain Questionnaire. Affective distress was assessed by the Global Severity Index from the Brief Symptom Inventory. Severity of depressive symptoms was derived from scores from the Center for Epidemiological Studies-Depression Scale. Pain beliefs and pain coping strategies were assessed by the Survey of Pain Attitudes and the Coping Strategies Questionnaire, respectively. Finally, self-report of pain-related disability was assessed by the Pain Disability Index.

RESULTS AND CONCLUSIONS

After controlling for relevant covariates, LOE was unrelated to pain intensity, severity of depressive symptoms, or affective distress, but was inversely related to self-reported disability. Persons with lower LOEs possessed a greater belief that pain is a "signal of harm," unrelated to emotional experience, disabling and uncontrollable. They also endorsed more passive and maladaptive coping strategies, including a tendency to catastrophize about their pain. Path analysis indicated that, after controlling for the influence of both the belief that pain is a "signal of harm" and catastrophizing on the association between LOE and disability, this relation loses statistical significance. These results suggest that pain-related cognitions mediate the relation between LOE and pain disability and that persons with lower LOEs are more likely to develop maladaptive pain beliefs and coping strategies.

Risk factors associated with the transition from acute to chronic occupational back pain

STUDY DESIGN

A prospective cohort study was conducted on workers claiming earnings-related compensation for low back pain. Information obtained at the time of the initial claim was linked to compensation status (still claiming or not claiming) 3 months later.

OBJECTIVE

To identify individual, psychosocial, and workplace risk factors associated with the transition from acute to chronic occupational back pain.

SUMMARY OF BACKGROUND DATA

Despite the magnitude of the economic and social costs associated with chronic occupational back pain, few prospective studies have investigated risk factors identifiable in the acute stage.

METHODS

At the time of the initial compensation claim, a self-administered questionnaire was used to gather information on a wide range of risk factors. Then 3 months later, chronicity was determined from claimants' computerized records.

RESULTS

The findings showed that 3 months after the initial assessment, 204 of the recruited 854 claimants (23.9%) still were receiving compensation payments. A combined multiple regression model of individual, psychosocial, and workplace risk factors demonstrated that severe leg pain (odds ratio [OR], 1.9), obesity (OR, 1.7), all three Oswestry Disability Index categories above minimal disability (OR, 3.1-4), a General Health Questionnaire score of at least 6 (OR, 1.9), unavailability of light duties on return to work (OR, 1.7), and a job requirement of lifting for three fourths of the day or more all were significant, independent determinants of chronicity (P < 0.05).

CONCLUSIONS

Simple self-report measures of individual, psychosocial, and workplace factors administered when earnings-related compensation for back pain is claimed initially can identify individuals with increased odds for development of chronic occupational disability.

Compensation and chronic pain

BACKGROUND

The literature contains many different viewpoints on the impact of compensation on recovery from chronic pain.

OBJECTIVE

What is the role of compensation in chronic pain and/or chronic pain disability?

METHODOLOGY

The literature search identified 11 observational studies to provide evidence about this question.

RESULTS

There is a paucity of high-quality data on the subject of the impact of compensation on chronic pain. This subject was reviewed under the headings of (1) injury claim rate and duration; (2) recovery; and (3) rehabilitation treatment programs. The studies were of subjects with musculoskeletal pain, mainly low back pain.

CONCLUSIONS

Filing a compensation claim for costs, retaining a lawyer, or higher pain intensities were limited predictors of longer claims (level 3). As the ratio of compensation to preinjury wage increases, there is moderate evidence (level 2) that the duration of the claim increases and that disability is more likely. Compensation status, particularly combined with higher pain intensities, is associated with poorer prognosis after rehabilitation treatment programs (level 3).

Determinants of duration of disability and return-to-work after work-related injury and illness: challenges for future research

BACKGROUND

The purpose of this review was to identify critical data and research needs in addressing the following question: What are the primary factors that affect the time lost from work, return-to-work (RTW), subsequent unemployment, and changes in occupation after disabling illness or injury?

METHODS

Review of the literature to identify research challenges originating from the multitude of disciplines, data sources, outcome measures, and methodological and analytical problems.

RESULTS

About 100 different determinants of RTW outcomes were identified. Their impact varies across different phases of the disablement process. Recommendations are provided for addressing five selected research challenges.

CONCLUSION

Interdisciplinary research needs to develop a comprehensive conceptual framework. Priority should be given to studies on specific domains of risk factors meeting five selection criteria: amenability to change; relevance to users of research; generalizability across health conditions, disability phases, and settings; "degree of promise" as derived from qualitative exploratory studies; and capacity to improve measurement instruments. Combining qualitative and quantitative research methods is necessary to bridge existing knowledge gaps.

Relationship between health services outcomes and social and economic outcomes in workplace injury and disease: data sources and methods

BACKGROUND

Understanding the mediating role of health care in mitigating social, economic and occupational role disability is a complex task.

METHODS

No single method of research will be successful in addressing all elements of this NORA research priority area. In this paper, we argue that research methods are needed which have the following components: (1) the detailed measurement of therapeutic intervention and the impacts of this intervention on clinical and functional health status using study designs which rule out competing explanations, (2) a longitudinal follow-up component which measures social, economic, and occupational role function following the conclusion of therapy, and (3) a commitment to execute studies across multiple settings to observe the variations in health care and in social and occupational role function that arise as a result of differences in labor market factors and employer and government policies.

CONCLUSIONS

More comprehensive portraits of the longitudinal trajectory of individual workers, social, economic and occupational role function following an occupational injury or illness will have significance for a large number of policy sectors.

The Boeing prospective study and beyond

STUDY DESIGN

The Boeing prospective study was reviewed. The Boeing prospective study, comprising two articles, was a large field study that explored why workers would or would not report occupational back pain problems.

OBJECTIVES

The most immediate objective was to determine the extent to which conclusions drawn from the Boeing prospective study withstand critical examination. The ultimate purpose of this review was to develop guidelines for field studies of back pain in industry.

SUMMARY OF BACKGROUND DATA

For more than a century, researchers have noted great variability among individuals in the reporting of back pain, but the explanations posed for this variability have been inconsistent. Because findings gain credibility roughly to the extent that they bear on the world outside the laboratory, field studies in particular hold great potential for clarifying the underlying explanation for individual variability in back pain reporting. The Boeing prospective study was a large and ambitious field study that examined this issue.

METHODS

The Boeing prospective study was examined through the lens of research conducted since it was published. The review used both the methodological and substantive literature.

RESULTS

The Boeing prospective study, based on a minority of workers originally solicited to participate in it (33-41%), accounted for 7% of the variation in why workers would or would not report a back pain problem. A number of issues that may have biased its results toward the null are examined.

CONCLUSIONS

The highlighting of the Boeing prospective study's limitations may be instructive not so much to criticize this one particular study but, rather, to anticipate problems that in general may be encountered in field studies of back pain in industry. Looking beyond the Boeing prospective study, the following guidelines for the conduct of such studies may be proposed: 1) Study designs should be based on explanations from which testable hypotheses may be derived; 2) Subgroups within the more general category of "back pain" should be delineated; 3) Both occupational exposures and psychosocial factors should be entered into the analysis; 4) Factors not apparent at the workplace should be considered; 5. Abstracts of articles should be carefully crafted.

Formal education and back pain: a review

OBJECTIVES

To summarise the scientific evidence on the relation between educational status and measures of the frequency and the consequences of back pain and of the outcomes of interventions among back pain patients, and to outline possible mechanisms that could explain such an association if found.

DESIGN

Sixty four articles published between 1966 and 2000 that documented the association of formal education with back pain were reviewed.

MAIN RESULTS

Overall, the current available evidence points indirectly to a stronger association of low education with longer duration and/or higher recurrence of back pain than to an association with onset. The many reports of an association of low education with adverse consequences of back pain also suggest that the course of a back pain episode is less favourable among persons with low educational attainment. Mechanisms that could explain these associations include variations in behavioural and environmental risk factors by educational status, differences in occupational factors, compromised "health stock" among people with low education, differences in access to and utilisation of health services, and adaptation to stress. Although lower education was not associated with the outcomes of interventions in major studies, it is difficult, in light of the current limited available evidence, to draw firm conclusions on this association.

CONCLUSION

Scientific evidence supports the hypothesis that less well educated people are more likely to be affected by disabling back pain. Further study of this association may help advance our understanding of back pain as well as understanding of the relation between socioeconomic status and disease as a general phenomenon.

Outcomes after surgery for thoracic outlet syndrome

PURPOSE

This study determined whether there is an association between psychological and socioeconomic characteristics and the long-term outcome of operative treatment for patients with sensory neurogenic thoracic outlet syndrome (N-TOS).

METHODS

Clinical records, preoperative psychological testing results, and long-term follow-up questionnaire data were reviewed for consecutive patients who underwent surgery for N-TOS from 1990 to 1999. Multivariate logistic regression models were developed as a means of identifying independent risk factors for postoperative disability.

RESULTS

Operative decompression of the brachial plexus via a supraclavicular approach was performed for upper extremity pain and paresthesia with no mortality and minimal morbidity in 170 patients. After an average follow-up period of 47 months, 65% of patients reported improved symptoms, and 64% of patients were satisfied with their operative outcome. However, 35% of patients remained on medication, and 18% of patients were disabled. Preoperative factors associated with persistent disability include major depression (odds ratio [OR], 15.7; P =.02), not being married (OR, 7.9; P =.04), and having less than a high school education (OR, 8.1; P =.09).

CONCLUSION

Operative decompression was beneficial for most patients. Psychological and social factors, including depression, marital status, and education, are associated with self-reported disability. The impact of the preoperative treatment of depression on the outcome of TOS decompression should be studied prospectively.