Simon Dagenais

A systematic review of low back pain cost of illness studies in the United States and internationally

BACKGROUND CONTEXT The economic burden of low back pain (LBP) is very large and appears to be growing. It is not possible to impact this burden without understanding the strengths and weaknesses of the research on which these costs are calculated. PURPOSE To conduct a systematic review of LBP cost of illness studies in the United States and internationally. STUDY DESIGN/SETTING Systematic review of the literature. METHODS Medline was searched to uncover studies about the direct or indirect costs of LBP published in English from 1997 to 2007. Data extracted for each eligible study included study design, population, definition of LBP, methods of estimating costs, year of data, and estimates of direct, indirect, or total costs. Results were synthesized descriptively. RESULTS The search yielded 147 studies, of which 21 were deemed relevant; 4 other studies and 2 additional abstracts were found by searching reference lists, bringing the total to 27 relevant studies. The studies reported on data from Australia, Belgium, Japan, Korea, the Netherlands, Sweden, the UK, and the United States. Nine studies estimated direct costs only, nine indirect costs only, and nine both direct and indirect costs, from a societal (n=18) or private insurer (n=9) perspective. Methodology used to derive both direct and indirect cost estimates differed markedly among the studies. Among studies providing a breakdown on direct costs, the largest proportion of direct medical costs for LBP was spent on physical therapy (17%) and inpatient services (17%), followed by pharmacy (13%) and primary care (13%). Among studies providing estimates of total costs, indirect costs resulting from lost work productivity represented a majority of overall costs associated with LBP. Three studies reported that estimates with the friction period approach were 56% lower than with the human capital approach. CONCLUSIONS Several studies have attempted to estimate the direct, indirect, or total costs associated with LBP in various countries using heterogeneous methodology. Estimates of the economic costs in different countries vary greatly depending on study methodology but by any standards must be considered a substantial burden on society. This review did not identify any studies estimating the total costs of LBP in the United States from a societal perspective. Such studies may be helpful in determining appropriate allocation of health-care resources devoted to this condition.

Synthesis of recommendations for the assessment and management of low back pain from recent clinical practice guidelines

BACKGROUND CONTEXT Low back pain (LBP) is a prevalent, costly, and challenging condition to manage. Clinicians must choose among numerous assessment and management options. Several recent clinical practice guidelines (CPGs) on LBP have attempted to inform these decisions by evaluating and summarizing the best available supporting evidence. The quality and consistency of recommendations from these CPGs are currently unknown. PURPOSE To conduct a systematic review of recent CPGs and synthesize their recommendations on assessing and managing LBP for clinicians. STUDY DESIGN/SETTING Systematic review. METHODS Literature search using MEDLINE, National Guidelines Clearinghouse, National Institute for Clinical Excellence, Internet search engines, and references of known articles. Only CPGs related to both assessment and management of LBP written in English were eligible; CPGs that summarized evidence from before the year 2000 were excluded. Data related to methods and recommendations for assessment and management of LBP were abstracted independently by two reviewers. Methodological quality was assessed using the Appraisal of Guidelines Research and Evaluation (AGREE) instrument by two reviewers. RESULTS The search uncovered 669 citations, of which 95 were potentially relevant and 10 were included in the review; 6 discussed acute LBP, 6 chronic LBP, and 6 LBP with neurologic involvement. Methods used to develop CPGs varied, but the overall methodological quality was high as defined by AGREE scores. Recommendations for assessment of LBP emphasized the importance of ruling out potentially serious spinal pathology, specific causes of LBP, and neurologic involvement, as well as identifying risk factors for chronicity and measuring the severity of symptoms and functional limitations, through the history, physical, and neurologic examination. Recommendations for management of acute LBP emphasized patient education, with short-term use of acetaminophen, nonsteroidal anti-inflammatory drugs, or spinal manipulation therapy. For chronic LBP, the addition of back exercises, behavioral therapy, and short-term opioid analgesics was suggested. Management of LBP with neurologic involvement was similar, with additional consideration given to magnetic resonance imaging or computed tomography to identify appropriate candidates willing to undergo epidural steroid injections or decompression surgery if more conservative approaches are not successful. CONCLUSIONS Recommendations from several recent CPGs regarding the assessment and management of LBP were similar. Clinicians who care for patients with LBP should endeavor to adopt these recommendations to improve patient care. Future CPGs may wish to invite coauthors from targeted clinician user groups, increase patient participation, update their literature searches before publication, conduct their own quality assessment of studies, and consider cost-effectiveness and other aspects in their recommendations more explicitly.

Causal assessment of occupational lifting and low back pain: results of a systematic review

BACKGROUND CONTEXT Low back pain (LBP) is a common and disabling musculoskeletal disorder that often occurs in a working-age population. Determining the precise causation of LBP remains difficult. Any attempt to implicate a specific occupational activity in the genesis of LBP requires a methodologically rigorous approach. PURPOSE To conduct a systematic review of the scientific literature focused on evaluating the causal relationship between occupational sitting and LBP. STUDY DESIGN Systematic review of the literature using Medline, EMBASE, CINAHL, Cochrane Library, Occupational Safety and Health database, grey literature, hand-searching occupational health journals, reference lists of included studies, and content experts. Evaluation of study quality using a modified version of the Newcastle-Ottawa Scale. Summary levels of evidence supporting Bradford-Hill criteria for different categories of sitting and types of LBP. SAMPLES Studies reporting an association between occupational sitting and LBP. OUTCOME MEASURES Numerical association between different levels of exposure to occupational sitting and the presence or severity of LBP. METHODS A systematic review was performed to identify, evaluate, and summarize the literature related to establishing a causal relationship, according to Bradford-Hill criteria, between occupational sitting and LBP. RESULTS This search yielded 2,766 citations. Twenty-four studies met the inclusion/exclusion criteria and five were high-quality studies, including two case-controls and three prospective cohorts. Strong, consistent evidence was found for no association between occupational sitting and LBP. A moderate level of evidence was found for the absence of any dose-response trend. Risk estimates evaluating temporality were not statistically significant. Biological plausibility was not discussed in these studies. No evidence was available to assess the experiment criterion. CONCLUSIONS This review failed to uncover high-quality studies to support any of the Bradford-Hill criteria to establish causality between occupational sitting and LBP. Strong and consistent evidence did not support criteria for association, temporality, and dose response. Based on these results, it is unlikely that occupational sitting is independently causative of LBP in the populations of workers studied.

Evidence-informed management of chronic low back pain with spinal manipulation and mobilization

The management of chronic low back pain (CLBP) has proven very challenging in North America, as evidenced by its mounting socioeconomic burden. Choosing among available nonsurgical therapies can be overwhelming for many stakeholders, including patients, health providers, policy makers, and third-party payers. Although all parties share a common goal and wish to use limited health-care resources to support interventions most likely to result in clinically meaningful improvements, there is often uncertainty about the most appropriate intervention for a particular patient. To help understand and evaluate the various commonly used nonsurgical approaches to CLBP, the North American Spine Society has sponsored this special focus issue of The Spine Journal, titled Evidence Informed Management of Chronic Low Back Pain Without Surgery. Articles in this special focus issue were contributed by leading spine practitioners and researchers, who were invited to summarize the best available evidence for a particular intervention and encouraged to make this information accessible to nonexperts. Each of the articles contains five sections (description, theory, evidence of efficacy, harms, and summary) with common subheadings to facilitate comparison across the 24 different interventions profiled in this special focus issue, blending narrative and systematic review methodology as deemed appropriate by the authors. It is hoped that articles in this special focus issue will be informative and aid in decision making for the many stakeholders evaluating nonsurgical interventions for CLBP.

Systematic Review of the Prevalence of Radiographic Primary Hip Osteoarthritis

Hip osteoarthritis is a common cause of musculoskeletal pain in older adults and may result in decreased mobility and quality of life. Although the presentation of hip osteoarthritis varies, surgical management is required when the disease is severe, longstanding, and unresponsive to nonoperative treatments. For stakeholders to plan for the expected increased demand for surgical procedures related to hip osteoarthritis, including arthroplasty, it is important to first understand its prevalence. We conducted a systematic review by searching MEDLINE® and EMBASE to identify recent English language articles reporting on the prevalence of radiographic primary hip osteoarthritis in the general adult population; references including studies and primary studies from previous systematic reviews were also searched. This strategy yielded 23 studies reporting 39 estimates of overall prevalence ranging from 0.9% to 27% with a mean of 8.0% and a standard deviation of 7.0%. Heterogeneity was noted in study populations, eligibility criteria, age and gender distribution, type of radiographs, and method of diagnosis. Although the association between radiographic hip osteoarthritis and the need for eventual surgical management is still unclear, this study supports assertions that hip osteoarthritis is a prevalent condition whose treatment will continue to place important demands on health services.

Causal assessment of occupational bending or twisting and low back pain: results of a systematic review

BACKGROUND CONTEXT Low back pain (LBP) is a common musculoskeletal disorder that often occurs in the working-age population. Although numerous physical activities have been implicated in its etiology, determining causation remains challenging and requires a methodologically rigorous approach. PURPOSE To conduct a systematic review focused on establishing a causal relationship between occupational bending or twisting and LBP. STUDY DESIGN A systematic review of the literature using Medline, Embase, CINAHL, Cochrane Library, and Occupational Safety and Health database, gray literature, hand-searching occupational health journals, reference lists of included studies, and experts. Evaluation of methodological quality using a modified Newcastle-Ottawa Scale for observational studies. Summary levels of evidence for each of the Bradford-Hill criteria for causality for each category of bending or twisting and type of LBP. SAMPLE Studies reporting an association between occupational bending or twisting and LBP. OUTCOME MEASURES Numerical association between different levels of exposure to bending or twisting and the presence or severity of LBP. METHODS A systematic review was performed to identify, evaluate, and summarize the literature related to establishing a causal relationship, according to Bradford-Hill criteria, between occupational bending or twisting and LBP. RESULTS This search yielded 2,766 citations. Ten high-quality studies reported on bending and LBP. Five were case-control studies and five were prospective cohort studies. There was conflicting evidence for association, with five studies demonstrating significant associations in the majority of their risk estimates, but no evidence for consistency. Seven studies assessed dose response, with four studies demonstrating a nonsignificant dose-response trend. Four studies were able to assess temporality, but only one demonstrated significant risk estimates. Biological plausibility was discussed by two studies. There was no available evidence for experiment. Seven high-quality studies reported on twisting and LBP. Two were case-control studies and five were prospective cohort studies. Three studies reported significant associations in the majority of their risk estimates, with no evidence for consistency. Three studies demonstrated a nonsignificant dose-response trend. Two studies were able to assess temporality, but only one study was able to demonstrate significant risk estimates. Two studies discussed biological plausibility. There was no available evidence for experiment. CONCLUSIONS A summary of existing studies was not able to find high-quality studies that satisfied more than three of the Bradford-Hill criteria for causation for either occupational bending or twisting and LBP. Conflicting evidence in multiple criteria was identified. This suggests that specific subcategories could contribute to LBP. However, the evidence suggests that occupational bending or twisting in general is unlikely to be independently causative of LBP.

Causal assessment of awkward occupational postures and low back pain: results of a systematic review

BACKGROUND CONTEXT Low back pain (LBP) is a prevalent and costly musculoskeletal disorder that often occurs in the working-age population. Although numerous physical activities have been implicated in its complex etiology, determining causation remains challenging and requires a methodologically rigorous approach. PURPOSE To conduct a systematic review of the scientific literature focused on establishing a causal relationship between awkward occupational postures and LBP. STUDY DESIGN Systematic review of the literature using MEDLINE, EMBASE, CINAHL, Cochrane Library, and Occupational Safety and Health database, gray literature, hand-searching occupational health journals, reference lists of included studies, and experts. Evaluation of methodological quality using a modified Newcastle-Ottawa Scale for observational studies. Summary levels of evidence for each of the Bradford Hill criteria for causality for each category of awkward occupational posture and type of LBP. SAMPLE Studies reporting an association between awkward occupational postures and LBP. OUTCOME MEASURES Numerical association between different levels of exposure to awkward occupational postures and the presence or severity of LBP. METHODS A systematic review was performed to identify, evaluate, and summarize the literature related to establishing a causal relationship, according to Bradford Hill criteria, between awkward occupational postures and LBP. RESULTS This search yielded 2,766 citations. Eight high-quality studies reported on awkward occupational postures and LBP. Three were case-control studies, one was cross-sectional, and four were prospective cohort studies. There was strong evidence for consistency of no association between awkward occupational postures and LBP, with only two studies demonstrating significant associations in most of their risk estimates compared with six studies reported mainly nonsignificant associations. Two studies assessed dose response, with one study demonstrating a nonsignificant dose-response trend. Three studies were able to assess temporality, but all demonstrated nonsignificant risk estimates. Biological plausibility was discussed by two studies. There was no available evidence to assess the experiment criterion for causality. CONCLUSIONS There was strong evidence from six high-quality studies that there was no association between awkward postures and LBP. Similarly, there was strong evidence from three high-quality studies that there was no temporal relationship. Moreover, subgroup analyses identified only a handful of studies that demonstrated only weak associations and no evidence for other aspects of causality in certain specific subcategories. It is therefore unlikely that awkward occupational postures are independently causative of LBP in the populations of workers studied.

Systematic review: occupational physical activity and low back pain

BACKGROUND Although various occupational physical activities are suspected of contributing to low back pain (LBP), causal relationships have not been confirmed, complicating adjudication of work injuries, return to work instructions and preventive efforts. AIMS To summarize eight systematic review (SR) reports that examined evidence supporting causal relationships between bending/twisting, awkward postures, sitting, standing/walking, carrying, pushing/pulling, lifting and manual handling/assisting patients and LBP. METHODS A literature search was conducted to identify eligible studies. Methodological quality was assessed using a modified Newcastle-Ottawa Scale (NOS). Levels of evidence supporting factors for causation were examined using a Bradford Hill framework. Results were presented in eight SR reports, each focused on one or more related physical activities. This study summarizes findings from those reports and offers clinicians an overview. RESULTS Collectively, the eight SR reports included 99 studies. None found strong evidence supporting a causal relationship between any occupational physical activity considered and LBP. Conflicting evidence was found between LBP and bending, twisting, lifting or pushing/pulling, but only for statistical association, not causation. Strong evidence against a causal relationship was found between LBP and manual handling/assisting patients, awkward postures, carrying, sitting, standing or walking. CONCLUSIONS Although occupational physical activities are suspected of causing LBP, findings from the eight SR reports did not support this hypothesis. This may be related to insufficient or poor quality scientific literature, as well as the difficulty of establishing causation of LBP. These population-level findings do not preclude the possibility that individuals may attribute their LBP to specific occupational physical activities.

Causal assessment of occupational standing or walking and low back pain: results of a systematic review

BACKGROUND CONTEXT Low back pain (LBP) is a widespread musculoskeletal condition that frequently occurs in the working-age population. Numerous occupational physical activities have been implicated in its etiology. PURPOSE To conduct a systematic review establishing a causal relationship between occupational standing or walking and LBP. STUDY DESIGN Systematic review of the literature. SAMPLE Studies reporting an association between occupational standing or walking and LBP. OUTCOME MEASURES Numerical association between exposure to standing or walking and the presence of LBP. METHODS A systematic review was performed to identify, evaluate, and summarize the literature related to establishing a causal relationship, according to Bradford-Hill criteria for causality, between occupational standing or walking and LBP. A search was conducted using MEDLINE, Embase, CINAHL, Cochrane Library, and Occupational Safety and Health database, gray literature, hand-searching occupational health journals, reference lists of included studies, and expert knowledge. Evaluation of methodological quality was performed using a modified Newcastle-Ottawa Scale. RESULTS This search yielded 2,766 citations. Eighteen studies met the inclusion criteria. Five were high-quality studies related to standing, and two were high-quality studies related to walking. For occupational standing and LBP, there was moderate to strong evidence against the association criterion, the only study examining dose response did not support this criterion, four studies examining temporality failed to support this criterion, and only one study discussed the biological plausibility criterion. For occupational walking and LBP, there was moderate evidence against a causal relationship with respect to the association, temporality, dose response, and biological plausibility criteria. No studies assessed the experiment criterion for these activities. CONCLUSIONS A summary of existing studies was not able to find any high-quality studies that satisfied more than two of the Bradford-Hill causation criteria for occupational standing or walking and LBP. Based on the evidence reviewed, it is unlikely that occupational standing or walking is independently causative of LBP in the populations of workers studied.

Causal assessment of workplace manual handling or assisting patients and low back pain: results of a systematic review

BACKGROUND CONTEXT Low back pain (LBP) is a common musculoskeletal disorder associated with a considerable social and economic burden within the working-age population. Despite an unclear etiology, numerous physical activities are suspected of leading to LBP. Declaring a causal relationship between occupational activities and LBP remains challenging and requires a methodologically rigorous approach. PURPOSE To conduct a systematic review focused on assessing the potentially causal relationship between workplace manual handling or assisting patients and LBP. STUDY DESIGN Systematic review of the literature. SAMPLES Studies reporting an association between workplace manual handling or assisting patients and LBP. OUTCOME MEASURES Numerical association between different levels of exposure to manual handling or assisting patients, and the presence or severity of LBP. METHODS A systematic review was conducted using Medline, EMBASE, CINAHL, Cochrane Library, and Occupational Safety and Health database, gray literature, hand-searching occupational health journals, reference lists of included studies, and content experts. The methodological quality of each study was assessed using a modified Newcastle-Ottawa Scale (NOS) for observational studies. The overall level of evidence supporting various Bradford-Hill criteria for causality for each category of manual handling or assisting patients and type of LBP was then evaluated. Studies were deemed of higher quality if they received a score of five or more on the modified NOS and used appropriate statistical analysis methods. RESULTS This search yielded 2,766 citations, and 32 studies met the eligibility criteria. Three high-quality studies reported on manual handling and LBP, including two prospective cohorts and one cross-sectional design. None demonstrated a significant association in most of their multivariate risk estimates. One study was able to assess dose-response and temporality, but its results did not support these criteria. Only one study discussed the biological plausibility of this association. Four high-quality studies evaluated assisting patients and LBP, including two case-controls, one cross-sectional, and one prospective cohort design. These studies were consistent in reporting no significant association. Two studies demonstrated a nonsignificant dose-response trend, and two studies discussed the biological plausibility of this association. No studies were able to demonstrate the temporality or experiment criteria. CONCLUSIONS The studies reviewed did not support a causal association between workplace manual handling or assisting patients and LBP in a Bradford-Hill framework. Conflicting evidence in specific subcategories of assisting patients was identified, suggesting that tasks such as assisting patients with ambulation may possibly contribute to LBP. It appears unlikely that workplace manual handling or assisting patients is independently causative of LBP in the populations of workers studied.