Details on the association between heavy lifting and low back pain

Abstract

In a series of articles [ 1 Wai K. Roffey D.M. Bishop P. et al. Causal assessment of occupational bending or twisting and low back pain: results of a systematic review. Spine J. 2010; 10: 76-88 Abstract Full Text Full Text PDF PubMed Scopus (117) Google Scholar , 2 Roffey D.M. Wai E.K. Bishop P. et al. Causal assessment of awkward occupational postures and low back pain: results of a systematic review. Spine J. 2010; 10: 89-99 Abstract Full Text Full Text PDF PubMed Scopus (105) Google Scholar , 3 Roffey D.M. Wai E.K. Bishop P. et al. Causal assessment of occupational sitting and low back pain: results of a systematic review. Spine J. 2010; 10: 252-261 Abstract Full Text Full Text PDF PubMed Scopus (125) Google Scholar , 4 Roffey D.M. Wai E.K. Bishop P. et al. Causal assessment of occupational standing or walking and low back pain: results of a systematic review. Spine J. 2010; 10: 262-272 Abstract Full Text Full Text PDF PubMed Scopus (74) Google Scholar , 5 Roffey D.M. Wai E.K. Bishop P. et al. Causal assessment of occupational pushing or pulling and low back pain: results of a systematic review. Spine J. 2010; 10: 544-553 Abstract Full Text Full Text PDF PubMed Scopus (47) Google Scholar , 6 Wai E.K. Roffey D.M. Bishop P. et al. Causal assessment of occupational lifting and low back pain: results of a systematic review. Spine J. 2010; 10: 554-566 Abstract Full Text Full Text PDF PubMed Scopus (124) Google Scholar , 7 Wai E.K. Roffey D.M. Bishop P. et al. Causal assessment of occupational carrying and low back pain: results of a systematic review. Spine J. 2010; 10: 628-638 Abstract Full Text Full Text PDF PubMed Scopus (58) Google Scholar , 8 Roffey D.M. Wai E.K. Bishop P. et al. Causal assessment of workplace manual handling or assisting patients and low back pain: results of a systematic review. Spine J. 2010; 10: 639-651 Abstract Full Text Full Text PDF PubMed Scopus (78) Google Scholar ], systematic reviews have evaluated the causal relationships between several physical occupational factors and low back pain (LBP). The authors state, “Synthesizing results from multiple studies requires careful consideration of specific research questions, study designs, study populations, study of methodological quality, and specific types of statistical analyses” [ [6] Wai E.K. Roffey D.M. Bishop P. et al. Causal assessment of occupational lifting and low back pain: results of a systematic review. Spine J. 2010; 10: 554-566 Abstract Full Text Full Text PDF PubMed Scopus (124) Google Scholar ]. We certainly agree. As the authors include a study from our group [ [9] Andersen J.H. Haahr J.P. Frost P. Risk factors for more severe regional musculoskeletal symptoms: a two-year prospective study of a general working population. Arthritis Rheum. 2007; 56: 1355-1364 Crossref PubMed Scopus (344) Google Scholar ] in the basis of high-quality studies in several of the reviews [ 2 Roffey D.M. Wai E.K. Bishop P. et al. Causal assessment of awkward occupational postures and low back pain: results of a systematic review. Spine J. 2010; 10: 89-99 Abstract Full Text Full Text PDF PubMed Scopus (105) Google Scholar , 3 Roffey D.M. Wai E.K. Bishop P. et al. Causal assessment of occupational sitting and low back pain: results of a systematic review. Spine J. 2010; 10: 252-261 Abstract Full Text Full Text PDF PubMed Scopus (125) Google Scholar , 4 Roffey D.M. Wai E.K. Bishop P. et al. Causal assessment of occupational standing or walking and low back pain: results of a systematic review. Spine J. 2010; 10: 262-272 Abstract Full Text Full Text PDF PubMed Scopus (74) Google Scholar , 5 Roffey D.M. Wai E.K. Bishop P. et al. Causal assessment of occupational pushing or pulling and low back pain: results of a systematic review. Spine J. 2010; 10: 544-553 Abstract Full Text Full Text PDF PubMed Scopus (47) Google Scholar , 6 Wai E.K. Roffey D.M. Bishop P. et al. Causal assessment of occupational lifting and low back pain: results of a systematic review. Spine J. 2010; 10: 554-566 Abstract Full Text Full Text PDF PubMed Scopus (124) Google Scholar ], we want to question the interpretation of some of our study results. Concerning lifting and LBP, we found associations in both partly and fully adjusted models, and in our fully adjusted model, we reported hazard ratios going from 1.0 in the reference group, 1.2 in the medium-exposed group, and 1.5 (95% confidence interval: 1.0–2.3) in the highest exposure group. In the review, this is interpreted as “no significant associations.” Although the estimates are small, this conveys a significant exposure-response trend (p=.043). Furthermore, the analyses were made among participants with no or minor pain at baseline (n=1,513), and temporality was partly demonstrated, although we questioned the notion of incidence of regional musculoskeletal pain because nearly everyone has a bit of it from early age and further on. It would also be enlightening from reviews such as these to know which and why earlier studies were not included, for example [ 10 Macfarlane G.J. Thomas E. Papageorgiou A.C. et al. Employment and physical work activities as predictors of future low back pain. Spine. 1997; 22: 1143-1149 Crossref PubMed Scopus (185) Google Scholar , 11 Punnett L. Fine L.J. Keyserling W.M. et al. Back disorders and nonneutral trunk postures of automobile assembly workers. Scand J Work Environ Health. 1991; 17: 337-346 Crossref PubMed Scopus (460) Google Scholar ], perhaps by some additional references on the web page of the journal. Causal assessment of occupational lifting and low back pain: results of a systematic reviewThe Spine JournalVol. 10Issue 6PreviewLow back pain (LBP) is a disorder that commonly affects the working population, resulting in disability, health-care utilization, and a heavy socioeconomic burden. Although the etiology of LBP remains uncertain, occupational activities have been implicated. Evaluating these potentially causal relationships requires a methodologically rigorous approach. Occupational repetitive and/or heavy lifting is widely thought to be a risk factor for the development of LBP. Full-Text PDF Causal assessment of occupational bending or twisting and low back pain: results of a systematic reviewThe Spine JournalVol. 10Issue 1PreviewLow 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. Full-Text PDF Causal assessment of awkward occupational postures and low back pain: results of a systematic reviewThe Spine JournalVol. 10Issue 1PreviewLow 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. Full-Text PDF Causal assessment of occupational standing or walking and low back pain: results of a systematic reviewThe Spine JournalVol. 10Issue 3PreviewLow 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. Full-Text PDF Causal assessment of workplace manual handling or assisting patients and low back pain: results of a systematic reviewThe Spine JournalVol. 10Issue 7PreviewLow 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. Full-Text PDF Causal assessment of occupational carrying and low back pain: results of a systematic reviewThe Spine JournalVol. 10Issue 7PreviewOccupational low back pain (LBP) is a common musculoskeletal disorder that results in high healthcare use and a heavy societal burden from morbidity and medical costs. The etiology of LBP is unclear, although numerous physical activities in the workplace have been implicated in its development. Determining the causal relationship between LBP and specific occupational activities requires a rigorous methodological approach. Full-Text PDF Causal assessment of occupational pushing or pulling and low back pain: results of a systematic reviewThe Spine JournalVol. 10Issue 6PreviewLow back pain (LBP) is a prevalent and expensive musculoskeletal condition that predominantly occurs in working-age individuals of industrialized nations. Although numerous occupational physical activities have been implicated in its etiology, determining the causation of occupational LBP still remains a challenge. Full-Text PDF Causal assessment of occupational sitting and low back pain: results of a systematic reviewThe Spine JournalVol. 10Issue 3PreviewLow 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. Full-Text PDF ReplyThe Spine JournalVol. 11Issue 7PreviewWe wish to thank Drs Andersen and Haahr for their interest in our systematic reviews evaluating causal evidence between occupational physical activities and low back pain (LBP) [1–8]. Full-Text PDF