The latest Global Burden of Disease Study, published at the end of 2012, has highlighted the enormous global burden of low back pain. In contrast to the previous study, when it was ranked 105 out of 136 conditions, low back pain is now the leading cause of disability globally, ahead of 290 other conditions. It was estimated to be responsible for 58.2 million years lived with disability in 1990, increasing to 83 million in 2010. This chapter illustrates the ways that the Global Burden of Disease data can be displayed using the data visualisation tools specifically designed for this purpose. It also considers how best to increase the precision of future global burden of low back pain estimates by identifying limitations in the available data and priorities for further research. Finally, it discusses what should be done at a policy level to militate against the rising burden of this condition.
Introduction
The Global Burden of Disease Injuries, and Risk Factors (GBD) 2010 Study has been the most comprehensive effort to date to estimate summary measures of population health for the world, a venture that has involved hundreds of researchers from nearly 50 countries over a number of years *[1], *[2], *[3], *[4], *[5]. The overall summary measure of population health that the GBD uses, disability-adjusted life years (DALYs), combines data on mortality, measured as years of life lost due to premature mortality (YLLs), and years of life lived in less than ideal health, measured as years lived with disability (YLDs). YLDs are the number of incident cases, multiplied by the average duration of the condition (average number of years that the condition lasts until remission or death), multiplied by the disability weight (DW). In some instances, it is calculated by multiplying the number of prevalent cases by the DW.
For the GBD 2010 study, the 1990, 2005 and 2010 burden for 291 diseases and injuries in 187 countries and 21 regions of the world were estimated. This included five musculoskeletal conditions – low back pain, neck pain, osteoarthritis of the hip and/or knee, rheumatoid arthritis and gout and an ‘other musculoskeletal conditions’ category.
As well as allowing comparisons of overall population health across different settings over time, repeated measures of population health identify which conditions are contributing most to health loss in a given population (e.g., a region or country) and capture any changes that occur over time. These data are important in informing health policy and ensuring that the most burdensome health conditions receive appropriate attention. Despite strong evidence that low back pain is a highly prevalent, disabling and costly condition *[6], [7], [8], and the most common problem among the working population in high-income countries [9], the enormous global burden of low back pain has remained largely unrecognised and therefore underprioritised by many governments to date.
No burden estimates were made for low back pain in the original GBD 1990 study, while, for the GBD 2000–2004 updates, low back pain was ranked 105 out of 136 conditions, and estimated to contribute just 2.5 million YLDS to the global burden of disease [10]. The low ranking in comparison to other conditions may, in part, be explained by the fact that low back pain does not cause premature mortality. However, there are several other possible contributors to the significant underestimation of the problem [11], [12], *[13]. Two of the three health states used to define burden from low back pain referred to an intervertebral disc disorder (episode of intervertebral disc displacement or herniation and chronic intervertebral disc disorder). As well as requiring imaging to detect these, the presence of disc pathology has been demonstrated to have poor correlation with symptoms [14]. In addition, mild nonspecific low back pain (a common state with a substantial global impact) was excluded, duration of low back pain was assumed to be 4 days, incidence was extrapolated from period prevalence, the DWs were lower and there was a paucity of suitable data for many countries.
New, more advanced methods have been used in the most recent GBD study to estimate disease burden. As well, unlike previous GBD studies that relied solely upon a core team of scientists and methodologists to produce the GBD estimates, approximately 37 expert groups were formed to provide content expertise to the process. The expert groups assumed primary responsibility for defining the case definition and conducting systematic reviews of the incidence, prevalence and disabling sequelae of the conditions in their content areas. DWs and mortality working groups were also established to derive study-wide DW and mortality estimates, respectively.
In a previous issue of this journal devoted to low back pain, we described the process that the Low Back Pain Expert Group for the GBD 2010 study undertook to derive a case definition of low back pain and a set of discrete health states to describe the severity levels and disabling consequences of low back pain [12]. In a subsequent issue devoted to the epidemiology of rheumatic disease, we described the methods and brief results of a series of systematic reviews undertaken to determine the incidence, remission and prevalence of low back pain throughout the world [11] Other papers present findings of the systematic review of the global prevalence of low back pain [6] and the development and testing of a risk of a bias tool developed specifically to assess potential bias in prevalence studies [15]. Following on from the publication of the overall GBD study results in The Lancet at the end of 2012 *[1], *[2], *[3], *[4], the Musculoskeletal Expert Group has reported the specific methods that were used for estimating burden of the GBD musculoskeletal conditions [16] as well as more detailed results outlining the global burden of each of these conditions including low back pain [13].
To aid in the rapid dissemination of results, the GBD study data are now publicly available as a series of data visualisations, which can be accessed at http://www.healthmetricsandevaluation.org [17]. As new information becomes available, these visualisations are being continuously updated. The tools to access the data were developed by the Institute for Health Metrics and Evaluation (IHME), an independent global health research centre based at the University of Washington and supported by the Bill & Melinda Gates Foundation and the State of Washington. As well as its utility for decision makers, it is hoped that making the data accessible in this way will allow wider scrutiny of the results [17].
There are many ways to examine the GBD results using these data visualisations [17]. For example, users can produce a world map of low back pain showing YLDs or DALYs by region or country, or show the ranking of low back pain compared with other causes within a country, providing an easy-to-understand appreciation of the relative importance of low back pain within each country. The data can also be broken down by gender and age and can show changes that occur over time (1990–2010), such as how low back pain burden has changed over time in comparison with other conditions globally and within regions or individual countries.
This chapter places the findings from the GBD study relating to low back pain in context and illustrates the ways that the data can be displayed using the data visualisation tools developed by the IHME. Of note, as the data visualisations are being continuously updated, there are minor differences between the published GBD study results and the data visualisation screenshots we present (taken 31 August 2013). We will also consider and make recommendations for how further research could improve the precision of global burden of low back pain estimates in the future. Finally, the chapter will discuss what should be done at a policy level to militate against the rising burden of this condition.
Section snippets
Global and regional results
As reported elsewhere, low back pain was estimated to contribute 58.2 million (M) DALYs (95% uncertainty intervals (UI): 39.9–78.1M) to the global burden of disease in 1990, ranking it as the 11th leading global contributor to years lost from premature mortality or years lived in ill health *[1], *[13]. For 2010, low back pain was ranked the sixth leading contributor to overall disease burden, estimated to be 83.0M (95% UI: 56.6–111.9M) DALYs. Fig. 1 displays the rankings for the top 10
Exploring the GBD results for low back pain at the country level
As outlined by the GBD Country Collaboration [17], the availability of standardised estimates of disease burden at a country level provides an opportunity to undertake comparative assessments between countries and also provides national policymakers with the necessary data to identify their most pressing health priorities and the ability to benchmark their performance in addressing them. However, it is important to note that while estimates for all causes are available for each country,
Data limitations
One of the significant methodological innovations in GBD 2010 was the quantification of uncertainty (an approximate range of variation) in the updated burden estimates [1]. This provides an indication of the precision of the estimates of burden of a given condition. It takes into account the number of studies that have contributed to the data and uncertainty from all sources entering the estimation of burden, for example, prevalence, incidence, duration, remission, disability weighting,
Policy recommendations
Given the immense global burden of low back pain identified in the GBD 2010 study, and the likelihood that it will continue to grow, it seems essential to now give it the attention it deserves. A series of strategies have been proposed that could be undertaken by the Bone and Joint Decade to achieve this goal at the global level [42]. They have recommended that the World Health Organization (WHO) make low back (and neck) pain a priority within their non-communicable diseases initiatives. This
Summary
The enormous global burden of low back pain has gone largely unrecognised by many policymakers. The results of the latest GBD study confirms its place as the greatest contributor to disability worldwide, adding 10.7% of total years lost due to disability, and this is likely to increase as the population ages. Data from the GBD study is available online and data visualisation tools allow individuals to explore the results at a global, regional or country level. These data provide an
Conflicts of interest
The authors have no declarations of conflict of interest.
Research Agenda
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Adoption of the international consensus definition of low back pain for all new population-based prevalence surveys
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Adoption of the international consensus's brief definition of low back pain for all new general health surveys
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Cross-cultural validation of low back pain definitions into other languages
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Develop standardised definitions of incidence, remission and ‘an episode’ of low back pain and obtain international consensus
Acknowledgements
The GBD project was supported by the Bill & Melinda Gates Foundation (DH) and the Australian Commonwealth Department of Health and Ageing (LM). RB is partially supported by an Australian National Health and Medical Research (NHMRC) Council Practitioner Fellowship and DH was supported by a National Health and Medical Research Council (NHMRC) Postgraduate Scholarship.
Perceptually, there is a discrepancy between research evidence and clinical physiotherapy practice for supporting self-management in people with low back pain (LBP).
This study aimed to explore physiotherapists’ understanding of LBP; ascertain their knowledge of self-management concepts; and explore their attitudes and beliefs about supporting self-management for LBP within present physiotherapy practice in private and hospital settings.
Interpretive Description qualitative methodology, involving in-depth data interpretation to clinical practice, was used.
Semi-structured interviews with physiotherapists throughout New Zealand were conducted via video conferencing. Data was analysed and themes were defined.
Seventeen physiotherapists (24–65 years old), with between one and 40+ years of experience, participated. Four main themes were defined: 1) Evolving understanding of LBP, 2) apportioning responsibility, 3) self-management is important, 4) understanding self-management.
Novel findings from this research demonstrate examples of attitudes and beliefs that determine when and how self-management for people with LBP is implemented. Due to these attitudes and beliefs, physiotherapists may not consistently provide supported self-management for people with LBP. Participants had good understanding of LBP but lacked a contemporary knowledge of the natural history and tended to apportion responsibility for persistent or recurrent episodes to the person with LBP. Physiotherapists should be encouraged to assimilate more contemporary research evidence into their expectations of recovery for LBP. Further education about the role of physiotherapists in supporting self-management, the core components of self-management, including engagement, and reflection upon individual unconscious bias should be encouraged.
High intensity training (HIT) improves disability and physical fitness in persons with chronic nonspecific low back pain (CNSLBP). However, it remains unclear if HIT affects pain processing and psychosocial factors.
To evaluate 1) the effects of HIT on symptoms of central sensitization and perceived stress and 2) the relationship of symptoms of central sensitization and perceived stress with therapy success, at six-month follow-up, in persons with CNSLBP.
This is a secondary analysis of a previously published randomized controlled trial. Persons with CNSLBP (n = 51, age=43.6y) completed the Central Sensitization Inventory (CSI) and Perceived Stress Scale (PSS) at baseline (PRE) and six months after 12-week of HIT consisting of concurrent exercise therapy (FU). Two groups were formed based on CSI scores (low-CSI/high-CSI). First, linear mixed models were fitted for each outcome, with time and groups as covariates. Multiple comparisons were executed to evaluate group (baseline), time (within-group), and interaction (between-group) effects. Second, correlation and regression analyses were performed to evaluate if baseline and changes in CSI/PSS scores were related to therapy success, operationalized as improvements on disability (Modified Oswestry Disability Index), and pain intensity (Numeric Pain Rating Scale).
Total sample analyses showed a decrease in both CSI and PSS. Within-group analyses showed a decrease of CSI only in the high-CSI group and a decrease of PSS only in the low-CSI group. Between-group analyses showed a pronounced decrease favouring high-CSI (mean difference: 7.9; 95%CI: 2.1, 12.7) and no differences in PSS (mean difference: 0.1; 95%CI: -3.0, 3.2). CSI, but not PSS, was weakly related to therapy success.
HIT improves symptoms of central sensitization in persons with CNSLBP. This effect is the largest in persons with clinically relevant baseline CSI scores. HIT also decreases perceived stress.
Excellent research in all fields, including spine surgery, exists in many different regions and languages. This study seeks to determine the relative number of spine related peer-reviewed publications throughout the world based on language.
Peer-reviewed publications from the eleven most prolific languages in regard to both the number of peer-reviewed spine publications indexed in PubMed and total peer-reviewed publications from 1950-2020 were identified in PubMed.
29,711,547 peer-reviewed publications were analyzed for the languages of interest with 870,404 (3.0%) of those being spine related peer-reviewed publications. Between 1988 and 2019, non-English language peer-reviewed publications decreased annually for both all peer-reviewed publications and spine related peer-reviewed publications by 44% and 36%, respectively. All medical and spine specific peer reviewed publications in English compared to non-English publications have increased by 7.22 and 6.35 times since 1988, respectively. While the ratio of non-English to English spine related publications decreased in all eleven countries, the percentage of the number of spine specific publications written in Chinese (462%), Portuguese (378%), and Spanish (88%) have increased by the listed percentages.
While the proportion of peer-reviewed publications in the field of spine surgery written in English have increased over the past several decades, there are many non-English language peer-reviewed publications each year, particularly in Chinese. Although the rapid increase in the proportion of English spine related publications is beneficial to English speaking physicians and researchers, further research is necessary to understand the impact on non-English speaking physicians and researchers.
Spinal disorders are some of the most prevalent, disabling, and costly conditions worldwide.1
Given the paucity of relevant data, the Council of State Neurosurgical Societies Workforce Committee launched a survey of neurosurgeons to assess patterns in activity restriction recommendations following spine surgery; the ultimate goal was to optimize and potentially standardize these recommendations. The aim of this initial study was to determine current practices in activity restrictions and return to work guidelines following common spinal procedures.
The survey included questions regarding general demographics and practice data, postoperative bracing/orthosis utilization, and guidelines for postoperative return to different levels of activity/types of work following specific spine surgery interventions. A spectrum of typical spine surgeries was assessed, including microdiscectomy, anterior cervical discectomy and fusion (ACDF), and lumbar fusion, both open and minimal invasive surgery (MIS) approaches.
There was significant interprocedure and intraprocedure variation in the neurosurgeons’ recommendations for postoperative activity and return to work recommendations after various spinal surgery procedures. Comparisons of the different surgical procedures evaluated revealed significant differences in cervical collar use (more often used following ≥2-level ACDF than single-level ACDF; P < 0.001), return to both sedentary and light physical work (greater restriction with ≥2-level ACDF than with single-level ACDF; P < 0.001), and return to a light exercise regimen (sooner following MIS versus open lumbar fusion; P < 0.001).
This survey demonstrated little consistency regarding return to work recommendations, general activity restrictions, and orthosis utilization following common spinal surgical procedures. Addressing this issue also has significant implications for the societal and personal costs of spine surgery.
Emergency nurses are at higher risk than the average worker of experiencing lumbar pain. This is the first study to undertake real time monitoring to quantify lumbar movements of nurses working in the emergency department (ED).
Emergency nurses at a single Australian ED were recruited for a prospective observational case study. Participants worked in four discrete clinical areas of the ED; In-charge, triage, resuscitation, and cubicles. Data collected included participant demographics, lumbar pain pre- and post-shift, and real-time recording of lumbar movements.
Sixty-two nurses participated. There were statistically significant differences in time spent standing (p = 0.005), sitting (p ≤ 0.001) and in locomotion (moving) (p ≤ 0.001) when compared by clinical role. Triage nurses spent over half their shift sitting, had the most sustained (> 30 s) flexions (60+ degrees) and had a median of 4 periods of uninterrupted sitting (10−30 mins) per shift.
Differences in movement demands were identified based on various clinical roles in the ED. Triage was associated with greater periods of uninterrupted sitting and with greater degrees of sustained flexion, both of which are predictors for back pain. This study provides foundation evidence that triage may not be the most appropriate location for staff returning from back injury.