Low back pain is an extremely common symptom experienced by people of all ages.1, 2, 3 In 2015, the global point prevalence of activity-limiting low back pain was 7·3%, implying that 540 million people were affected at any one time. Low back pain is now the number one cause of disability globally.4 The largest increases in disability caused by low back pain in the past few decades have occurred in low-income and middle-income countries, including in Asia, Africa, and the Middle East,5 where health and social systems are poorly equipped to deal with this growing burden in addition to other priorities such as infectious diseases.
Rarely can a specific cause of low back pain be identified; thus, most low back pain is termed non-specific. Low back pain is characterised by a range of biophysical, psychological, and social dimensions that impair function, societal participation, and personal financial prosperity. The financial impact of low back pain is cross-sectoral because it increases costs in both health-care and social supports systems.6 Disability attributed to low back pain varies substantially among countries, and is influenced by social norms, local health-care approaches, and legislation.7 In low-income and middle-income countries, formal and informal social-support systems are negatively affected. While in high-income countries, the concern is that the prevalent health-care approaches for low back pain contribute to the overall burden and cost rather than reducing it.8 Spreading high-cost health-care models to low-income and middle-income countries will compound rather than alleviate the burden. Low back pain is therefore an urgent global public health concern.
Key messages
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Low back pain is an extremely common symptom in populations worldwide and occurs in all age groups, from children to the elderly population
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Low back pain was responsible for 60·1 million disability-adjusted life-years in 2015, an increase of 54% since 1990, with the biggest increase seen in low-income and middle-income countries
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Disability from low back pain is highest in working age groups worldwide, which is especially concerning in low-income and middle-income countries where informal employment is common and possibilities for job modification are limited
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Most episodes of low back pain are short-lasting with little or no consequence, but recurrent episodes are common and low back pain is increasingly understood as a long-lasting condition with a variable course rather than episodes of unrelated occurrences
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Low back pain is a complex condition with multiple contributors to both the pain and associated disability, including psychological factors, social factors, biophysical factors, comorbidities, and pain-processing mechanisms
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For the vast majority of people with low back pain, it is currently not possible to accurately identify the specific nociceptive source
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Lifestyle factors, such as smoking, obesity, and low levels of physical activity, that relate to poorer general health, are also associated with occurrence of low back pain episodes
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Costs associated with health care and work disability attributed to low back pain vary considerably between countries, and are influenced by social norms, health-care approaches, and legislation
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The global burden of low back pain is projected to increase even further in coming decades, particularly in low-income and middle-income countries
Against this backdrop, we present a series of two papers and a Viewpoint. The aim of this paper is to present a current understanding of what low back pain is, its burden and global impact, as well as an overview of causes and the course of low back pain. The evidence for the effectiveness of current treatments and promising new directions for managing low back pain is presented in paper two,9 and the Viewpoint is a worldwide call to action.10
The approach for this Series involved the constitution of a team of leading international experts on back pain from different professional backgrounds and from countries around the globe who convened for a workshop in Buxton, UK, in June, 2016, to outline the structure of each paper. For this paper, we identified scientific studies using broad search terms in MEDLINE (PubMed) and Scopus. To identify potentially relevant papers from low-income and middle-income countries, we also searched Google Scholar and the African Index Medicus Database. To minimise selection bias and to ensure high-quality evidence was selected, systematic reviews were preferred and sought when possible. However, we also used information from large population-based cohorts, international clinical guidelines, and the Global Burden of Disease (GBD) 2015 study. Primary research from low-income and middle-income regions excluded from systematic reviews was also referenced where appropriate.