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

Comparisons of lumbosacral kinematics among non-specific chronic low back pain subgroups and healthy during prolonged sitting: A cross-sectional observational study

BACKGROUND

The literature has suggested a variety of postural changes of the spine that possibly contribute to the increase in back pain during sitting in persons with non-specific chronic low back pain (NS-CLBP). However, the heterogeneity of NS-CLBP persons has made the ability to attribute pain increase to a particular sitting posture very difficult. Therefore, the purpose of this study was to compare lumbosacral kinematics and their roles in pain increase among homogenous NS-CLBP subgroups and healthy controls over a 1-h sitting period.

METHODS

Twenty NS-CLBP subjects with motor control impairment [10 classified as having flexion pattern (FP) disorder, and 10 with active extension pattern (AEP) disorder], and 10 healthy controls participated in the study. Subjects underwent a 1-h sitting protocol on a standard office chair. Lumbosacral postures including sacral tilt, third lumbar vertebrae (L3) position, and relative lower lumbar angle were recorded using two-dimensional inclinometers over the 1-h period. Perceived back-pain intensity was measured using a visual analog scale every 10 min throughout the sitting period.

RESULTS

All study groups (FP, AEP and healthy controls) significantly differed from each other in the measured lumbosacral kinematics at the beginning as well as at the end of the sitting period (p ≤ 0.05). Only the NS-CLBP subgroups showed significant changes in the lumbosacral kinematics across the 1-h sitting period (p < 0.01), and that the directions of change occurred toward end spinal postures (lumbar kyphosis for FP subgroup and lumbar lordosis for the AEP subgroup). In addition, both NS-CLBP subgroups reported a similarly significant increase in pain through mid-sitting (p < 0.001). However, after mid-sitting, the AEP subgroup reported much less increase in pain level that was accompanied by a significant decrease in the lumbar lordotic postures (p = 0.001) compared to FP subgroup.

CONCLUSION

The present study's findings suggest that each NS-CLBP subgroup presented with differently inherent sitting postures. These inherently dysfunctional postures coupled with the directional changes in the lumbosacral kinematics toward the extreme ranges across the 1-h sitting period, might explain the significant increase in pain among subgroups.

A novel motorized office chair causes low-amplitude spinal movements and activates trunk muscles: A cross-over trial

INTRODUCTION

Inactivity and long periods of sitting are common in our society, even though they pose a health risk. Dynamic sitting is recommended to reduce this risk. The purpose of this study was to investigate the effect of continuous passive motion (CPM) conducted by a novel motorized office chair on lumbar lordosis and trunk muscle activation, oxygen uptake and attentional control.

STUDY DESIGN

Randomized, single-session, crossover with two periods/conditions.

METHODS

Twenty office workers (50% women) sat for one hour on the motorized chair, one half with CPM, the other not. The starting condition (CPM/no CPM) was switched in half of the sample. The participants were equipped with a spirometric cart, surface EMG, the Epionics SPINE system and performed a computer-based test for attentional control (AX-CPT). Outcomes were lumbar sagittal movements and posture, number of trunk muscle activations, attentional control and energy expenditure.

RESULTS

The CPM of the chair causes frequent low-amplitude changes in lumbar lordosis angle (moved: 498 ± 133 vs. static: 45 ± 38) and a higher number of muscle activations. A periodic movement pattern of the lumbar spine according to the movement of the chair was observed in every participant, although, sitting behavior varied highly between individuals. Attentional control was not altered in the moved condition (p = .495; d = .16). Further, oxygen uptake did not increase higher than 1.5 MET.

CONCLUSION

The effects of the motorized chair can be particularly useful for people with static sitting behavior. Further studies should investigate, whether CPM provides the assumed beneficial effects of dynamic sitting on the spine.

[Chronic Back Pain]

Chronic back pain is one of the most common diseases in Germany. In many cases, no morphological change is found, so that the genesis remains unspecific in over 90% of patients. This article is intended to provide an overview of drug therapy as well as non-drug measures and summarizes the corresponding guideline recommendations.

Associations between observed time sitting at work and musculoskeletal symptoms: a repeated-measures study of manufacturing workers

Time sitting at work is known to affect health overall, but its specific effects on musculoskeletal symptoms are unclear. We evaluated the relationship between observed time sitting at work and self-reported musculoskeletal symptoms among 195 manufacturing workers. Longer time sitting at work was significantly associated with lower prevalence of neck/shoulder (prevalence ratio [PR] = 0.70, 95% confidence interval [CI] [0.68, 0.72]; p < 0.001) and arm/wrist/hand (PR = 0.46, 95% CI [0.31, 0.69]; p < 0.001) musculoskeletal symptoms. Associations remained largely unchanged after adjusting for job type or occupational postures and load. Time sitting at work was associated with musculoskeletal symptoms, and should be taken into consideration as part of interventions to prevent musculoskeletal disorders (MSDs) and promote health of manufacturing workers.

Causal Relationship Between the Risk Factors and Work-Related Musculoskeletal Disorders Among Professional Drivers: A Systematic Review

OBJECTIVE

This review evaluates the evidence on the strength of causal relationship between categories of risk factors (RFs) and work-related musculoskeletal disorders (WRMSDs) among professional drivers.

BACKGROUND

A compilation of evidence on the causal relationship between RFs and WRMSDs among professional drivers is lacking.

METHODS

A systematic search of the literature was conducted in major electronic data bases that include Medline (1946 + via OvidSP), Embase (1974 + OvidSP), CINAHL (1982+), AMED, and Web of Science. The methodological quality of the studies was assessed and scored. A descriptive analysis on the categories of RFs associated with WRMSDs was conducted. The Bradford-Hill causation criteria and evidence interpretation tool were used to evaluate the causal relationship between RFs and WRMSDs in professional drivers.

RESULTS

Among the 54 studies reviewed, a strong evidence suggests a causal relationship between RFs such as whole-body vibration, awkward postures, lifting tasks, manual material handling, job stress, job demand, and previous pain episodes with WRMSDs. Moderate evidence was observed on RFs such as uncomfortable seat and low job satisfaction. The evidence on causal relationship between RFs such as years of professional driving, driving duration, and individual characteristics such as age and body mass index was inconclusive.

CONCLUSION

There is strong to moderate evidence on the causal relationship between the physical and psychosocial RFs and WRMSDs among professional drivers.

APPLICATION

Potential application of this review highlights evidence to occupational health practitioners, policy makers, and stakeholders on the strength of causal relationship between RFs and WRMSDs among professional drivers.

Evaluating Different Measures of Low Back Pain Among U.S. Manual Materials Handling Workers: Comparisons of Demographic, Psychosocial, and Job Physical Exposure

OBJECTIVE

To examine differences in demographic, psychosocial, and job physical exposure risk factors between multiple low back pain (LBP) outcomes in a prospective cohort of industrial workers.

BACKGROUND

LBP remains a leading cause of lost industrial productivity. Different case definitions involving pain (general LBP), medication use (M-LBP), seeking healthcare (H-LBP), and lost time (L-LBP) are often used to study LBP outcomes. However, the relationship between these outcomes remains unclear.

METHOD

Demographic, health status, psychosocial, and job physical exposure risk factors were quantified for 635 incident-eligible industrial workers. Incident cases of LBP outcomes and pain symptoms were quantified and compared across the four outcomes.

RESULTS

Differences in age, gender, medical history, and LBP history were found between the four outcomes. Most incident-eligible workers (67%) suffered an LBP outcome during follow-up. Cases decreased from 420 for LBP (25.4 cases/100 person-years) to 303 for M-LBP (22.0 cases/100 person-years), to 151 for H-LBP (15.6 cases/100 person-years), and finally to 56 for L-LBP (8.7 cases/100 person-years). Conversely, pain intensity and duration increased from LBP to H-LBP. However, pain duration was relatively lower for L-LBP than for H-LBP.

CONCLUSION

Patterns of cases, pain intensity, and pain duration suggest the influence of the four outcomes. However, few differences in apparent risk factors were observed between the outcomes. Further research is needed to establish consistent case definitions.

APPLICATION

Knowledge of patterns between different LBP outcomes can improve interpretation of research and guide future research and intervention studies in industry.

Influence of a Sacroiliac Belt on Pain and Functional Impairment in Patients With Low Back Pain: A Randomized Trial

Objective

The purpose of this study was to assess the protective influence of the Serola Sacroiliac Belt on pain and functional impairment in individuals with low back pain (LBP) during 5 days of strenuous manual labor.

Methods

Thirty-three participants (mean ± standard deviation: age, 43.2 ± 11.4 years; height, 1.74 ± 0.11 m; body mass index, 88.3 ± 16.7 kg) with LBP were randomized to either condition A (wearing the Serola Sacroiliac Belt during a 10-minute daily repeated strenuous lifting task) during week 1 or condition B (not wearing a Serola Sacroiliac Belt during the same lifting task) in week 2 or vice versa. All 33 participants completed 1 week under condition A and 1 week under condition B for comparison. At the beginning and end of each week, the following dependent variables were measured: lumbar spine pain on a 0 to 10 Numeric Rating Scale (NRS), spine and thigh discomfort on a Nordic Musculoskeletal Questionnaire, and completion of a toe-touch surface electromyography flexion relaxation phenomenon test.

Results

During the week that participants used the Serola Sacroiliac Belt, spine pain increased 0.2 compared with 0.9 on the NRS for those who did not use the belt. No statistically significant difference was observed for Nordic Musculoskeletal Questionnaire data or the flexion relaxation phenomenon test in this study.

Conclusion

The findings of this preliminary study suggest participants using the Serola Sacroiliac Belt while performing a daily repeated lifting task had less progression of their LBP. However, this protective value did not meet the recommended NRS for minimally clinically important difference, and there was no effect on functional impairment.

Causal assessment in evidence synthesis: A methodological review of reviews

In fields (such as population health) where randomised trials are often lacking, systematic reviews (SRs) can harness diversity in study design, settings and populations to assess the evidence for a putative causal relationship. SRs may incorporate causal assessment approaches (CAAs), sometimes called 'causal reviews', but there is currently no consensus on how these should be conducted. We conducted a methodological review of self-identifying 'causal reviews' within the field of population health to establish: (1) which CAAs are used; (2) differences in how CAAs are implemented; (3) how methods were modified to incorporate causal assessment in SRs. Three databases were searched and two independent reviewers selected reviews for inclusion. Data were extracted using a standardised form and summarised using tabulation and narratively. Fifty-three reviews incorporated CAAs: 46/53 applied Bradford Hill (BH) viewpoints/criteria, with the remainder taking alternative approaches: Medical Research Council guidance on natural experiments (2/53, 3.8%); realist reviews (2/53, 3.8%); horizontal SRs (1/53, 1.9%); 'sign test' of causal mechanisms (1/53, 1.9%); and a causal cascade model (1/53, 1.9%). Though most SRs incorporated BH, there was variation in application and transparency. There was considerable overlap across the CAAs, with a trade-off between breadth (BH viewpoints considered a greater range of causal characteristics) and depth (many alternative CAAs focused on one viewpoint). Improved transparency in the implementation of CAA in SRs in needed to ensure their validity and allow robust assessments of causality within evidence synthesis.

Funeral Industry Workers' Work Health and Safety in Australia and Ireland

Funeral workers (FWs) work within increasingly medicalized and commodified death-management systems. This study explored Worker Health and Safety (WHS) impacts in contemporary death management on Australian and Irish FWs. Mixed methods combined a survey and interviews. Survey data were descriptively summarized, interviews thematically analyzed, and a schematic systems model developed of the combined results. Survey participants (n = 45) reported psychosocial hazards from work pressures, competition, and fatigue. Psychosocial hazards were more frequently reported than physical hazards by Australian FWs. Physical hazards were of greater concern to Irish FWs. Themes from 11 interviews were: Personal Attributes, Work Demands, and Socio-Cultural Context. All FWs reported conflicts between individual capacities, work demands, and resources, resulting in hazardous personal states including difficulty sleeping and stress. Respectfully manually handling human remains and "event management" demands for increasingly elaborate funerals created negative WHS impacts. This research informs risk management for FWs and other workers in the increasingly complex death-care industry.

Formulation of Japanese Orthopaedic Association (JOA) clinical practice guideline for the management of low back pain- the revised 2019 edition

BACKGROUND

The latest clinical guidelines are mandatory for physicians to follow when practicing evidence-based medicine in the treatment of low back pain. Those guidelines should target not only Japanese board-certified orthopaedic surgeons, but also primary physicians, and they should be prepared based entirely on evidence-based medicine. The Japanese Orthopaedic Association Low Back Pain guideline committee decided to update the guideline and launched the formulation committee. The purpose of this study was to describe the formulation we implemented for the revision of the guideline with the latest data of evidence-based medicine.

METHODS

The Japanese Orthopaedic Association Low Back Pain guideline formulation committee revised the previous guideline based on a method for preparing clinical guidelines in Japan proposed by Medical Information Network Distribution Service Handbook for Clinical Practice Guideline Development 2014. Two key phrases, "body of evidence" and "benefit and harm balance" were focused on in the revised version. Background and clinical questions were determined, followed by literature search related to each question. Appropriate articles were selected from all the searched literature. Structured abstracts were prepared, and then meta-analyses were performed. The strength of both the body of evidence and the recommendation was decided by the committee members.

RESULTS

Nine background and nine clinical qvuestions were determined. For each clinical question, outcomes from the literature were collected and meta-analysis was performed. Answers and explanations were described for each clinical question, and the strength of the recommendation was decided. For background questions, the recommendations were described based on previous literature.

CONCLUSIONS

The 2019 clinical practice guideline for the management of low back pain was completed according to the latest evidence-based medicine. We strongly hope that this guideline serves as a benchmark for all physicians, as well as patients, in the management of low back pain.

The relationship between low back pain and the basic lumbar posture at work: a retrospective cross-sectional study

PURPOSE

This study aimed to analyze the relationship between work-related lumbar posture (sitting, standing, walking, alternating posture) and LBP in workers.

METHODS

This is a retrospective study comprising 529 records of adult workers from a database of a private company. Predominant work-related lumbar posture was classified based on time spent in each posture. A total of 22 personal, occupational, clinical, and psychosocial covariates were evaluated. LBP symptoms in the last 12 months and during the last 7 days were the outcomes of the study. The multivariate analysis model evaluated the independent relationship between the work-related lumbar posture classification and other potential exposure factors with LBP.

RESULTS

The adjusted logistic regression model indicated that predominant walking reduced the likelihood to report LBP during the last 12 months when compared to standing (OR = 0.54; 95% CI 0.30, 0.99; p = 0.048), but there is no association between work-related postures and recent LBP. The adjusted analyses also revealed an association between LBP during the last 12 months and female sex, blue-collar task, frequently feeling tiredness, pain at any other body region previous 12 months, previous LBP, and monotonous work. Recent LBP was associated with female sex, pain at any other body region last 7 days, and previous LBP.

CONCLUSIONS

Standing posture increases the likelihood to report LBP during the last 12 months when compared to walking. LBP over previous year and during the previous 7 days was associated with personal and clinical factors.

Does treadmill workstation use affect user's kinematic gait symmetry?

The effects of treadmill workstation use on kinematic gait symmetry and computer work performance remain unclear. The purpose of this pilot study was to analyze the effects of treadmill workstation use on lower body motion symmetry while performing a typing task when compared to overground and treadmill walking. The lower body motion of ten healthy adults (6 males and 4 females) was recorded by a motion capture system. Hip, knee, and ankle joint rotations were computed and compared for each condition. Despite comparable lower body kinematic gait asymmetries across conditions, asymmetric knee flexion motions at early gait cycle were only found in treadmill workstation users (left knee significantly more flexed than the right one). This demonstrates that the interaction between walking and another task is dependent on the task cognitive content. Our findings suggest that lower body kinematic gait symmetry may be influenced by the use of treadmill workstations.

Musculoskeletal pain and sedentary behaviour in occupational and non-occupational settings: a systematic review with meta-analysis

BACKGROUND

Sedentary behaviour (SB; time spent sitting) is associated with musculoskeletal pain (MSP) conditions; however, no prior systematic review has examined these associations according to SB domains. We synthesised evidence on occupational and non-occupational SB and MSP conditions.

METHODS

Guided by a PRISMA protocol, eight databases (MEDLINE, CINAHL, PsycINFO, Web of Science, Scopus, Cochrane Library, SPORTDiscus, and AMED) and three grey literature sources (Google Scholar, WorldChat, and Trove) were searched (January 1, 2000, to March 17, 2021) for original quantitative studies of adults ≥ 18 years. Clinical-condition studies were excluded. Studies' risk of bias was assessed using the QualSyst checklist. For meta-analyses, random effect inverse-variance pooled effect size was estimated; otherwise, best-evidence synthesis was used for narrative review.

RESULTS

Of 178 potentially-eligible studies, 79 were included [24 general population; 55 occupational (incuding15 experimental/intervention)]; 56 studies were of high quality, with scores > 0.75. Data for 26 were meta-synthesised. For cross-sectional studies of non-occupational SB, meta-analysis showed full-day SB to be associated with low back pain [LBP - OR = 1.19(1.03 - 1.38)]. Narrative synthesis found full-day SB associations with knee pain, arthritis, and general MSP, but the evidence was insufficient on associations with neck/shoulder pain, hip pain, and upper extremities pain. Evidence of prospective associations of full-day SB with MSP conditions was insufficient. Also, there was insufficient evidence on both cross-sectional and prospective associations between leisure-time SB and MSP conditions. For occupational SB, cross-sectional studies meta-analysed indicated associations of self-reported workplace sitting with LBP [OR = 1.47(1.12 - 1.92)] and neck/shoulder pain [OR = 1.73(1.46 - 2.03)], but not with extremities pain [OR = 1.17(0.65 - 2.11)]. Best-evidence synthesis identified inconsistent findings on cross-sectional association and a probable negative prospective association of device-measured workplace sitting with LBP-intensity in tradespeople. There was cross-sectional evidence on the association of computer time with neck/shoulder pain, but insufficient evidence for LBP and general MSP. Experimental/intervention evidence indicated reduced LBP, neck/shoulder pain, and general MSP with reducing workplace sitting.

CONCLUSIONS

We found cross-sectional associations of occupational and non-occupational SB with MSP conditions, with occupational SB associations being occupation dependent, however, reverse causality bias cannot be ruled out. While prospective evidence was inconclusive, reducing workplace sitting was associated with reduced MSP conditions. Future studies should emphasise prospective analyses and examining potential interactions with chronic diseases.

PROTOCOL REGISTRATION

PROSPERO ID # CRD42020166412 (Amended to limit the scope).

Relationship between psychological factors and spinal motor behaviour in low back pain: a systematic review and meta-analysis

ABSTRACT

This meta-analysis investigated whether more negative psychological factors are associated with less spinal amplitude of movement and higher trunk muscle activity in individuals with low back pain. Furthermore, it examined whether pain intensity was a confounding factor in this relationship. We included studies that provided at least 1 correlation coefficient between psychological (pain-related fear, catastrophizing, depression, anxiety, and self-efficacy) and spinal motor behaviour (spinal amplitude and trunk muscle activity) measures. In total, 52 studies (3949 participants) were included. The pooled correlation coefficients (95% confidence interval; number of participants) were -0.13 (-0.18 to -0.09; 2832) for pain-related fear, -0.16 (-0.23 to -0.09; 756) for catastrophizing, -0.08 (-0.13 to -0.03; 1570) for depression, -0.08 (-0.30 to 0.14; 336) for anxiety, and -0.06 (-0.46 to 0.36; 66) for self-efficacy. The results indicated that higher levels of pain-related fear, catastrophizing, and depression are significantly associated with reduced amplitudes of movement and larger muscle activity and were consistent across subgroup and moderation analyses. Pain intensity did not significantly affect the association between these psychological factors and spinal motor behaviour and had a very small independent association with spinal motor behaviour. In conclusion, the very small effect sizes found in the meta-analyses question the role of psychological factors as major causes of spinal movement avoidance in low back pain. Experimental studies with more specific and individualized measures of psychological factors, pain intensity, and spinal motor behaviour are recommended.

Prevalence and Associated Factors of Low Back Pain Among Bank Workers in Gondar City, Northwest Ethiopia

Introduction

Low back pain is a very common health problem that most people experience at some point in their working life. It results in sick leave, disability, producing significant restrictions on usual activity and participation among many office workers. The working style of bank workers is sedentary mostly and the alignment of their chairs, table, and computers is not designed based on their health aspects which exposes them to low back pain.

Objective

This study aimed to assess the prevalence and associated factors of low back pain among bank workers in Gondar city.

Methods

Institution-based cross-sectional study was conducted from 20th October to 10th November 2020 at banks in Gondar city. A simple random sampling technique was employed to select 296 bank workers. A structured pretested self-administered questionnaire was used to collect data. Data were entered in epi-info version 7, analyzed using SPSS version 21, and presented by frequencies, percentages, and tables. Bivariable and multivariable analyses were employed using a binary logistic regression model. Variables with a p-value < 0.05 were considered as factors significantly associated and the odds ratio with a 95% CI was used to determine the strength of association.

Results

The prevalence of low back pain among bank workers in the last 12 months was 55.4%. Being female, work-related stress, lack of physical activity, using a fixed chair and a chair without an armrest, and lifting heavy objects increases the risk of developing low back pain.

Conclusion

The prevalence of low back pain among bank workers in Gondar city was high. It is better to establish a health screening team, avail a movable chair and a chair with an armrest, and give special attention to female workers and bank workers with stress, and do physical activity to reduce the risk of developing low back pain.

Perceived musculoskeletal discomfort and its association with postural shifts during 4-h prolonged sitting in office workers

This study examined the characteristics of perceived discomfort and postural shifts at different magnitudes during a 4-h sitting period and the association between perceived discomfort and number of postural shifts. Forty healthy participants continuously typed a standardized text passage at a computer work station for 4 h. Subjects rated perceived body discomfort using Borg's CR-10 scale in 10 body regions (i.e. neck, shoulder, elbow, wrist/hand, upper back, lower back, buttock, thigh, knee, and ankle/foot). A seat pressure mat device was used to gather seat pressure data during sitting. Postural shifts were determined by analysis of the dispersion index of both ischial tuberosities from seat pressure data. The threshold for a postural shift was set at ±10% and ±20%. Perceived discomfort in all body regions increased continuously during a 4-h sitting period. The body regions with the highest perceived discomfort were the low back, buttocks, upper back, thigh, and neck. The average (±SD) numbers of postural shifts during the 1st, 2nd, 3rd, and 4th hour of sitting were 14.8 ± 9.5, 17.8 ± 9.4, 18.2 ± 11.1, and 18.1 ± 9.8 shifts per hour for the 10% threshold, and were 4.8 ± 4.4, 6.0 ± 5.6, 7.4 ± 6.7, and 7.7 ± 6.6 shifts per hour for the 20% threshold, respectively. Prolonged sitting led to an increase in perceived musculoskeletal discomfort over time. The number of postural shifts at both magnitudes increased in the first 2 h of sitting and, in the second 2-h period of sitting, only the number of larger postural shifts (with 20% threshold) increased. The findings extend our understanding of sitting behaviors.

Does objectively measured prolonged standing for desk work result in lower ratings of perceived low back pain than sitting? A systematic review and meta-analysis

BACKGROUND

Prolonged sitting has been shown to induce transient low back pain (LBP). Height adjustable office desks now present the opportunity to replace sitting with standing in the workplace. Since standing has also been associated with LBP, this may not be an advisable alternative.

OBJECTIVE

To determine if objectively measured prolonged exposures to desk work while standing, compared to sitting, results in lower perceived LBP in healthy adults.

METHODS

A systematic search of several databases was conducted. Two independent reviewers screened titles/abstracts and conducted a quality assessment. The results of three studies were pooled using an inverse variance random-effects meta-analysis. Heterogeneity was tested using the Chi-squared test and I2 statistic.

RESULTS

Objectively measured prolonged standing postures during desk work did not induce significantly less perceived LBP compared to seated postures (standardized mean difference 0.60, 95% CI -0.68 to 1.87, p = 0.36.) There was significant heterogeneity, I2 = 90%).

CONCLUSIONS

It appears that replacing seated desk work postures with standing for prolonged periods of time would not be recommended. Larger studies, including a wider age range and health history, conducted in the field with objective measures is recommended to obtain more generalizable data on which to base ergonomic standards for work postures.

What Psychosocial and Physical Characteristics Differentiate Office Workers Who Develop Standing-Induced Low Back Pain? A Cross-Sectional Study

This study examines demographic, physical and psychosocial factors associated with an increase in low back pain (LBP) during a one-hour standing task. A cross-sectional survey with 40 office workers was conducted. The primary outcome was pain severity during a one-hour standing task recorded every 15 min using a 100 mm Visual Analogue Scale (VAS). Participants were defined as pain developers (PD), if they reported a change in pain of ≥10 mm from baseline, or non-pain developers (NPD). Physical outcomes included participant-rated and examiner-rated trunk and hip motor control and endurance. Self-report history of LBP, physical activity, psychosocial job characteristics, general health and pain catastrophising were collected. Fourteen participants were PD. Hip abduction, abdominal and spinal muscle endurance was lower for PD (p ≤ 0.05). PD had greater self-reported difficulty performing active hip abduction and active straight leg raise tests (p ≤ 0.04). Those reporting a lifetime, 12 month or 7-day history of LBP (p < 0.05) and lower self-reported physical function (p = 0.01) were more likely to develop LBP during the standing task. In conclusion, a history of LBP, reduced trunk and hip muscle endurance and deficits in lumbopelvic/hip motor control may be important to consider in office workers experiencing standing-induced LBP.

Assessment of causal link between psychological factors and symptom exacerbation in inflammatory bowel disease: a systematic review utilising Bradford Hill criteria and meta-analysis of prospective cohort studies

BACKGROUND

Psychological stress is a prevalent factor in inflammatory bowel disease (IBD) with detrimental effects on patients' quality of life and possibly disease course. Although the aetiology of symptom exacerbation in IBD has been explored, determining any causation between psychological stress and symptom worsening remains challenging and requires a methodologically rigorous approach.

AIM

The aim of this systematic review with meta-analysis was to determine a causal relationship between psychological stress and symptom exacerbation in IBD, subsequently utilising Bradford Hill's criteria (approach never used in this topic area before) to evaluate the likelihood of causal associations.

METHODS

Medline, EMBASE, CINAHL and PsycInfo were searched for relevant studies up to July 20, 2019. Data extraction and quality appraisal were performed by two independent reviewers. Results of all retained papers were presented as a narrative synthesis. A random-effect meta-analysis was conducted on studies meeting the criteria for meta-analysis. Bradford Hill criteria were applied to assess the causality of the relationship between all psychological factors and symptom exacerbation.

RESULTS

The searches yielded 2472 potential articles. Nineteen clinical prospective cohort studies were eligible for the narrative review with five suitable for the meta-analysis. Meta-analysis showed depression, anxiety and perceived stress did not have a statistically significant association with an increased risk of symptom exacerbation. Four of the Bradford Hill criteria were met which indicates that there is weak to moderate evidence of a causal association between all the psychological factors and disease activity. Inconsistent results and a dearth of studies using the same tools for measuring psychological factors suggest the need for more research to be done to facilitate more conclusive findings.

CONCLUSIONS

This original review utilising Bradford Hill criteria in addition to meta-analysis to evaluate the causality of relationship between psychological factors and symptom exacerbation in IBD provides evidence that psychological factors have a weak to moderate causal involvement in IBD symptom exacerbation. However, when combining this finding with the outcomes of the meta-analysis, we can say that the results were inconclusive. Interventions to reduce the associated psychological impact should be part of the treatment plan for patients with IBD.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42012003143.

Why do we need to investigate non-classical musicians to reduce the burden of musicians' musculoskeletal symptoms?

Musculoskeletal symptoms (MSSs) are common among professional musicians; however, most of the research has focused on orchestral/classical musicians. In some countries orchestral and classical musicians are in the minority; hence targeting research towards these specific sub-groups of musicians is unlikely to address the overall burden of musicians' MSSs, unless the research is generalizable to other types of musicians. This multidisciplinary narrative review seeks to answer the question: "why do we need to examine the MSSs of non-classical groups of performing musicians in order to reduce the burden of musicians' MSSs?". There are differences in the education, posture, tasks (e.g. military training for military band musicians, dancing for those in musical theatre), venues and management of MSSs for different types of musicians. Future research should compare classical and non-classical musicians in order to determine which specific sub-groups (e.g. military band musicians) have the greatest MSS burden, such that further research into the risk factors of and interventions for MSSs can be targeted towards the sub-groups of musicians with the greatest MSS burden. In doing so, we maximise the likelihood of being able to introduce interventions, policies and practice that reduce the burden of musicians' MSSs.

Association between objectively measured physical behaviour and neck- and/or low back pain: A systematic review

BACKGROUND AND OBJECTIVE

Clinical guidelines recommend physical activity to manage neck pain (NP) and low back pain (LBP). However, studies used to support these guidelines are based on self-reports of physical behaviour, which are prone to bias and misclassification. This systematic review aimed to investigate associations between objectively measured physical behaviour and the risk or prognosis of NP and/or LBP.

DATABASES AND DATA TREATMENT

Literature searches were performed in MEDLINE, Embase and Scopus from their inception until 18 January 2019. We considered prospective cohort studies for eligibility. Article selection, data extraction and critical appraisal were carried out by independent reviewers. Results were stratified on activity/sedentariness.

RESULTS

Ten articles out of 897 unique records identified met the inclusion criteria, of which eight studied working populations with mainly blue-collar workers. The overall results indicate that increased sitting time at work reduces the risk of NP and LBP while increased physical activity during work and/or leisure increases the risk of these conditions among blue-collar workers; however, associations were weak. Physical activity was not associated with prognosis of LBP (no studies investigated prognosis of NP). Most of the included articles have methodological shortcomings.

CONCLUSIONS

This review indicates that, among blue-collar workers, increased sitting at work may protect against NP and LBP while increased physical activity during work and/or leisure may increase this risk. There was no evidence supporting physical activity as a prognostic factor for LBP. Findings should be interpreted with caution due to the weak associations and few available studies with methodological shortcomings.

SIGNIFICANCE

Based on prospective cohort studies with objectively measured physical behaviour, this review questions the common notion that increased physical activity is associated with reduced risk or better prognosis of NP and/or LBP. We found that, among blue-collar workers, increased sitting time at work reduces the risk of NP and LBP, whereas physical activity somewhat increases the risk. Despite methodological shortcomings, there was consistency in the direction of the results, although high-quality articles reported the weakest associations. Systematic review registration: PROSPERO CRD42018100765.

Lumbar interspinous pressure pain threshold values for healthy young men and women and the effect of prolonged fully flexed lumbar sitting posture: An observational study

BACKGROUND

Low back pain (LBP) is a common condition with large burden worldwide. Exposure to prolonged sitting with a flexed lumbar posture has been suggested in the literature to be a potential risk factor for self-reported LBP. No study has previously investigated whether exposure to prolonged flexed sitting posture provokes discomfort/pain and decreased interspinous pressure pain thresholds for healthy young men and women without back pain, despite this being a suggested risk factor for LBP.

AIM

To investigate whether sitting in a prolonged flexed lumbar posture provokes discomfort and lowers interspinous pressure pain thresholds in the lumbar spine for healthy young men and women without previous LBP.

METHODS

This is a an observational before and after study of 26 participants (13 men, 13 women) between 20-35 years old. Algometry was used to examine the pain threshold for pressure applied between spinous processes of the lumbar spine L1-L5. Pressure algometer measures were performed in prone before and after participants were instructed to sit in a fully flexed posture for a maximum of 15 min or until discomfort was experienced in the low back (Borg CR10 = 7/10). Wilcoxon signed-rank test was used for analyze values from the before and after test conditions. Mann-Whitney U test was used to investigate potential gender difference.

RESULTS

Fully flexed lumbar spine sitting posture up to 15 min provoked temporary discomfort but the proportion of participants experiencing discomfort 7/10 in the low back was 62%. For all pain pressure threshold locations tested, there was a significant difference for the study population with moderate-large decreased (r = -0.56) pressure pain threshold after exposure to prolonged flexed sitting posture (P < 0.01). Comparisons between gender did not show any significant difference.

CONCLUSION

The result showed that exposure to fully flexed lumbar sitting posture for up to 15 min produced temporary discomfort in the low back in young healthy adults with no previous history of LBP and significantly reduced lumbar interspinous pressure pain thresholds. No gender-based differences were observed.

Association of Exposures to Seated Postures With Immediate Increases in Back Pain: A Systematic Review of Studies With Objectively Measured Sitting Time

OBJECTIVE

The purpose of this study was to conduct a systematic review of studies to determine whether sitting time measured objectively (by laboratory controlled time trial, direct observation, or wearable sensor) is associated with the immediate increase in low back pain (LBP) (determined by pain scale rating) in people >18 years of age.

METHODS

Four databases (PubMed, EMBASE, SPORTDiscus, and Cumulative Index to Nursing and Allied Health Literature) were searched from inception to September 1, 2018. Randomized controlled trials and cohort and cross-sectional studies, where objectively measured sitting time was temporally matched with a measure of LBP in adults, were included. Studies without a control session conducted on a separate day were excluded. Screening, full-text review, data extraction, and risk of bias assessment (Quality In Prognosis Studies) of included papers were performed independently by 2 reviewers, with a third available to resolve disagreements.

RESULTS

In total, 609 articles were identified, 361 titles/abstracts were screened,75 full-text articles were assessed for eligibility, and 10 met the inclusion criteria. All but 1 reported sitting time to be associated with an immediate increase in LBP. Six of these reported clinically relevant pain levels (n = 330). Half of the included studies were rated as having a low risk of bias and the remaining were rated as having a moderate risk of bias.

CONCLUSION

Prolonged sitting increases immediate reporting of LBP in adults; however, no conclusion between sitting and clinical episodes of LBP can be made. Based upon these findings, we recommend that future prospective studies should match objectively measured sitting with temporally related pain measurements to determine whether prolonged sitting can trigger a clinical episode of LBP.

Workplace interventions for increasing standing or walking for decreasing musculoskeletal symptoms in sedentary workers

BACKGROUND

The prevalence of musculoskeletal symptoms among sedentary workers is high. Interventions that promote occupational standing or walking have been found to reduce occupational sedentary time, but it is unclear whether these interventions ameliorate musculoskeletal symptoms in sedentary workers.

OBJECTIVES

To investigate the effectiveness of workplace interventions to increase standing or walking for decreasing musculoskeletal symptoms in sedentary workers.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, OSH UPDATE, PEDro, ClinicalTrials.gov, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) search portal up to January 2019. We also screened reference lists of primary studies and contacted experts to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs), cluster-randomised controlled trials (cluster-RCTs), quasi RCTs, and controlled before-and-after (CBA) studies of interventions to reduce or break up workplace sitting by encouraging standing or walking in the workplace among workers with musculoskeletal symptoms. The primary outcome was self-reported intensity or presence of musculoskeletal symptoms by body region and the impact of musculoskeletal symptoms such as pain-related disability. We considered work performance and productivity, sickness absenteeism, and adverse events such as venous disorders or perinatal complications as secondary outcomes.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened titles, abstracts, and full-text articles for study eligibility. These review authors independently extracted data and assessed risk of bias. We contacted study authors to request additional data when required. We used GRADE considerations to assess the quality of evidence provided by studies that contributed to the meta-analyses.

MAIN RESULTS

We found ten studies including three RCTs, five cluster RCTs, and two CBA studies with a total of 955 participants, all from high-income countries. Interventions targeted changes to the physical work environment such as provision of sit-stand or treadmill workstations (four studies), an activity tracker (two studies) for use in individual approaches, and multi-component interventions (five studies). We did not find any studies that specifically targeted only the organisational level components. Two studies assessed pain-related disability. Physical work environment There was no significant difference in the intensity of low back symptoms (standardised mean difference (SMD) -0.35, 95% confidence interval (CI) -0.80 to 0.10; 2 RCTs; low-quality evidence) nor in the intensity of upper back symptoms (SMD -0.48, 95% CI -.096 to 0.00; 2 RCTs; low-quality evidence) in the short term (less than six months) for interventions using sit-stand workstations compared to no intervention. No studies examined discomfort outcomes at medium (six to less than 12 months) or long term (12 months and more). No significant reduction in pain-related disability was noted when a sit-stand workstation was used compared to when no intervention was provided in the medium term (mean difference (MD) -0.4, 95% CI -2.70 to 1.90; 1 RCT; low-quality evidence). Individual approach There was no significant difference in the intensity or presence of low back symptoms (SMD -0.05, 95% CI -0.87 to 0.77; 2 RCTs; low-quality evidence), upper back symptoms (SMD -0.04, 95% CI -0.92 to 0.84; 2 RCTs; low-quality evidence), neck symptoms (SMD -0.05, 95% CI -0.68 to 0.78; 2 RCTs; low-quality evidence), shoulder symptoms (SMD -0.14, 95% CI -0.63 to 0.90; 2 RCTs; low-quality evidence), or elbow/wrist and hand symptoms (SMD -0.30, 95% CI -0.63 to 0.90; 2 RCTs; low-quality evidence) for interventions involving an activity tracker compared to an alternative intervention or no intervention in the short term. No studies provided outcomes at medium term, and only one study examined outcomes at long term. Organisational level No studies evaluated the effects of interventions solely targeted at the organisational level. Multi-component approach There was no significant difference in the proportion of participants reporting low back symptoms (risk ratio (RR) 0.93, 95% CI 0.69 to 1.27; 3 RCTs; low-quality evidence), neck symptoms (RR 1.00, 95% CI 0.76 to 1.32; 3 RCTs; low-quality evidence), shoulder symptoms (RR 0.83, 95% CI 0.12 to 5.80; 2 RCTs; very low-quality evidence), and upper back symptoms (RR 0.88, 95% CI 0.76 to 1.32; 3 RCTs; low-quality evidence) for interventions using a multi-component approach compared to no intervention in the short term. Only one RCT examined outcomes at medium term and found no significant difference in low back symptoms (MD -0.40, 95% CI -1.95 to 1.15; 1 RCT; low-quality evidence), upper back symptoms (MD -0.70, 95% CI -2.12 to 0.72; low-quality evidence), and leg symptoms (MD -0.80, 95% CI -2.49 to 0.89; low-quality evidence). There was no significant difference in the proportion of participants reporting low back symptoms (RR 0.89, 95% CI 0.57 to 1.40; 2 RCTs; low-quality evidence), neck symptoms (RR 0.67, 95% CI 0.41 to 1.08; two RCTs; low-quality evidence), and upper back symptoms (RR 0.52, 95% CI 0.08 to 3.29; 2 RCTs; low-quality evidence) for interventions using a multi-component approach compared to no intervention in the long term. There was a statistically significant reduction in pain-related disability following a multi-component intervention compared to no intervention in the medium term (MD -8.80, 95% CI -17.46 to -0.14; 1 RCT; low-quality evidence).

AUTHORS' CONCLUSIONS

Currently available limited evidence does not show that interventions to increase standing or walking in the workplace reduced musculoskeletal symptoms among sedentary workers at short-, medium-, or long-term follow up. The quality of evidence is low or very low, largely due to study design and small sample sizes. Although the results of this review are not statistically significant, some interventions targeting the physical work environment are suggestive of an intervention effect. Therefore, in the future, larger cluster-RCTs recruiting participants with baseline musculoskeletal symptoms and long-term outcomes are needed to determine whether interventions to increase standing or walking can reduce musculoskeletal symptoms among sedentary workers and can be sustained over time.

Work-Related Exposures and Sickness Absence Trajectories: A Nationally Representative Follow-up Study among Finnish Working-Aged People

The contribution of physically demanding work to the developmental trajectories of sickness absence (SA) has seldom been examined. We analyzed the associations of 12 physical work exposures, individually and in combination, with SA trajectories among the occupationally active in the Finnish nationally representative Health 2000 survey. We included 3814 participants aged 30–59 years at baseline, when exposure history to work-related factors was reported. The survey and interview responses were linked with the annual number of medically confirmed SA spells through 2002–2008 from national registries. Trajectory analyses identified three SA subgroups: 1 = low (54.6%), 2 = slowly increasing (33.7%), and 3 = high (11.7%). After adjustments, sitting or use of keyboard >1 year was inversely associated with the high SA trajectory (odds ratio, OR, 0.57; 95% 95% confidence interval, CI, 0.43–0.77). The odds of belonging to the trajectory of high SA increased with an increasing number of risk factors, and was highest for those with ≥4 physical workload factors (OR 2.71; 95% CI 1.99–3.69). In conclusion, these findings highlight the need to find ways to better maintain the work ability of those in physically loading work, particularly when there occurs exposure to several workload factors.

Risk Factors for Low Back Pain in Childhood and Adolescence: A Systematic Review

OBJECTIVES

To identify factors associated with low back pain (LBP) in children and adolescents.

MATERIALS AND METHODS

A systematic review was conducted (Prospero CRD42016038186). Observational studies analyzing LBP risk factors among participants aged between 9 and 16 were searched for in 13 electronic databases and 8 specialized journals until March 31, 2016, with no language restrictions. In addition, references in the identified studies were manually tracked. All identified studies that included ≥50 participants aged 9 to 16, were reviewed. Their methodological quality was assessed by 2 reviewers separately, using validated tools, which scored, from worst to best, 0 to 100 for cross-sectional and 0 to 12 for cohort studies. A sensitivity analysis only included studies that had adjusted for confounders, had ≥500 participants, and had a methodological score of ≥50%.

RESULTS

A total of 5142 citations were screened and 61 studies, including 137,877 participants from 5 continents, were reviewed. Their mean (range) methodological scores were 74.56 (50 to 100) for cross-sectional studies and 7.36 (5 to 9) for cohort studies. The studies had assessed 35 demographic, clinical, biological, family, psychological, ergonomic, and lifestyle risk factors. The mean (range) prevalence of LBP ranged between 15.25% (3.20 to 57.00) for point prevalence and 38.98% (11.60 to 85.56) for lifetime prevalence. Results on the association between LBP and risk factors were inconsistent. In the sensitivity analysis, "older age" and "participation in competitive sports" showed a consistent association with LBP.

DISCUSSION

Future studies should focus on muscle characteristics, the relationship between body and backpack weights, duration of carrying the backpack, characteristics of sport practice, and which are the factors associated with specifically chronic pain.

Correlates of physical activity and sedentary behaviour in the Thai population: a systematic review

BACKGROUND

Given the importance of knowing the potential impediments and enablers for physical activity (PA) and sedentary behaviour (SB) in a specific population, the aim of this study was to systematically review and summarise evidence on individual, social, environmental, and policy correlates of PA and SB in the Thai population.

METHODS

A systematic review of articles written in Thai and English was conducted. Studies that reported at least one correlate for PA and/or SB in a healthy Thai population were selected independently by two authors. Data on 21 variables were extracted. The methodological quality of the included studies was assessed using the Newcastle-Ottawa Scale.

RESULTS

A total of 25,007 records were screened and 167 studies were included. The studies reported associations with PA for a total of 261 variables, mostly for adults and older adults. For most of the variables, evidence was available from a limited number of studies. Consistent evidence was found for individual-level and social correlates of PA in children/adolescents and adults and for individual-level correlates of PA in older adults. Self-efficacy and perceived barriers were consistently associated with PA in all age groups. Other consistently identified individual-level correlates in adults and older adults included self-rated general health, mental health, perceived benefits, and attitudes towards PA. Consistent evidence was also found for social correlates of PA in adults, including social support, interpersonal influences, parent/family influences, and information support. The influence of friendship/companionship was identified as a correlate of PA only in children/adolescents. A limited number of studies examined SB correlates, especially in older adults. The studies reported associations with SB for a total of 41 variables. Consistent evidence of association with SB was only found for obesity in adults. Some evidence suggests that male adults engage more in SB than females.

CONCLUSIONS

More Thai studies are needed on (i) PA correlates, particularly among children/adolescents, and that focus on environment- and policy-related factors and (ii) SB correlates, particularly among older adults. Researchers are also encouraged to conduct longitudinal studies to provide evidence on prospective and causal relationships, and subject to feasibility, use device-based measures of PA and SB.

Physiotherapist perceptions of optimal sitting and standing posture

BACKGROUND

Assessment of, and advice about, spinal posture is common when people with spinal pain present to physiotherapists. Most descriptions regarding optimal spinal posture have been qualitative in nature.

OBJECTIVES

To determine the beliefs of physiotherapists regarding optimal sitting and standing posture.

DESIGN

Online survey.

METHOD

544 Greek physiotherapists selected an optimal sitting (choice of seven) and standing (choice of five) posture, while providing justification for their choice.

RESULTS

Education regarding optimal sitting and standing posture was considered "considerably" or "very" important by 93.9% of participants. Three different sitting postures, and two different standing postures, were selected as the optimal posture by 97.5% and 98.2% of physiotherapists respectively. While this reflects a lack of complete consensus on optimal posture, the most commonly selected postures were all some variation of upright lordotic sitting, in contrast slouched spinal curves (sitting) or forward head posture (sitting and standing) almost never being selected as optimal. Interestingly, participants used similar arguments (e.g. natural curves, muscle activation) to justify their selection regardless of the spinal configuration of each selected posture.

CONCLUSIONS

These results reinforce previous data suggesting that upright lordotic sitting postures are considered optimal, despite a lack of strong evidence that any specific posture is linked to better health outcomes. While postural re-education may play a role in the management of spinal pain for some patients, awareness of such widespread and stereotypical beliefs regarding optimal posture may be useful in clinical assessment and management.

Acute effect of full time office work in real environment on postural actions and lumbar range of motion

INTRODUCTION

Prolonged sitting is often proposed as a risk factor for low back pain development. The purpose of this study was to evaluate the acute effect of full time office work on sensorimotor trunk functions.

METHODS

Seventeen healthy office workers participated in the study. Maximal lumbar flexion range of motion, anticipatory postural adjustments and postural reflex reactions were tested before and after full time office work in a real life environment.

RESULTS

There were longer onset latencies of postural reflexive reactions and decreased response amplitudes of anticipatory postural adjustments after full time office work, but these were significant only for the obliquus externus abdominis muscle. No changes in lumbar range of motion was found.

CONCLUSION

To our knowledge this is the first study that evaluates the effect of full time office work on postural actions and lumbar RoM. We found an absence of normal human circadian flexibility in the lumbar spine and some changes in postural actions. We propose that active trunk stiffness increase to compensate for decreased passive stiffness after prolonged seated work. Further studies are needed to confirm this assumption.

Familial factors predicting recovery and maintenance of physical activity in people with low back pain: Insights from a population-based twin study

BACKGROUND

It is unknown how familial factors influence the recovery from low back pain (LBP) and the maintenance activity behaviours. We aimed to investigate whether individual and within-family physical activity (PA) and sedentary behaviour influenced recovery from LBP, and maintenance of PA and sedentary behaviour in people with and without LBP.

METHODS

Longitudinal logistic regression analyses were performed on adult twins from the Washington State Twin Registry. First, individual and within-family (based on co-twin data) sufficient PA (at least 75 min of vigorous-intensity PA, or 150 min of moderate-intensity PA per week) and high leisure sitting time (≥3 hr/day) were our exposure variables (baseline). LBP within the past 3 months at follow-up defined non-recovery (outcome). Second, within-family sufficient PA and high leisure sitting time were our exposure variables(baseline) and our outcomes were individual PA and sitting time at follow-up. All analyses were adjusted for follow-up length (range: 1-7 years) and confounding variables.

RESULTS

Individual and within-family PA and sitting time were not associated with recovery. Within-family PA and sitting time predicted individual maintenance of PA (OR = 1.47, 95% CI: 1.17-1.84, n = 1,388 twins) and sitting time (OR = 1.41, 95% CI: 1.10-1.82, n = 1,534). Within-family PA and sitting time had the strongest effects on those without (OR = 1.79, 95% CI: 1.33-2.41, n = 788) and with LBP (OR = 1.90, 95% CI: 1.32-2.76, n = 698), respectively.

CONCLUSION

Having active family members increased the likelihood of continuing to be active (particularly for those without LBP), while having sedentary family members increased the likelihood of maintaining sedentary behaviours (particularly for those with LBP).

SIGNIFICANCE

This study was the first to investigate how familial activity behaviours influence recovery from LBP and ongoing activity behaviours. People with LBP living within a sedentary family likely require specific interventions to reduce their sedentary behaviours.

The Virtual-Spine Platform-Acquiring, visualizing, and analyzing individual sitting behavior

Back pain is a serious medical problem especially for those people sitting over long periods during their daily work. Here we present a system to help users monitoring and examining their sitting behavior. The Virtual-Spine Platform (VSP) is an integrated system consisting of a real-time body position monitoring module and a data visualization module to provide individualized, immediate, and accurate sitting behavior support. It provides a comprehensive spine movement analysis as well as accumulated data visualization to demonstrate behavior patterns within a certain period. The two modules are discussed in detail focusing on the design of the VSP system with adequate capacity for continuous monitoring and a web-based interactive data analysis method to visualize and compare the sitting behavior of different persons. The data was collected in an experiment with a small group of subjects. Using this method, the behavior of five subjects was evaluated over a working day, enabling inferences and suggestions for sitting improvements. The results from the accumulated data module were used to elucidate the basic function of body position recognition of the VSP. Finally, an expert user study was conducted to evaluate VSP and support future developments.

A scoping review of biopsychosocial risk factors and co-morbidities for common spinal disorders

OBJECTIVE

The purpose of this review was to identify risk factors, prognostic factors, and comorbidities associated with common spinal disorders.

METHODS

A scoping review of the literature of common spinal disorders was performed through September 2016. To identify search terms, we developed 3 terminology groups for case definitions: 1) spinal pain of unknown origin, 2) spinal syndromes, and 3) spinal pathology. We used a comprehensive strategy to search PubMed for meta-analyses and systematic reviews of case-control studies, cohort studies, and randomized controlled trials for risk and prognostic factors and cross-sectional studies describing associations and comorbidities.

RESULTS

Of 3,453 candidate papers, 145 met study criteria and were included in this review. Risk factors were reported for group 1: non-specific low back pain (smoking, overweight/obesity, negative recovery expectations), non-specific neck pain (high job demands, monotonous work); group 2: degenerative spinal disease (workers' compensation claim, degenerative scoliosis), and group 3: spinal tuberculosis (age, imprisonment, previous history of tuberculosis), spinal cord injury (age, accidental injury), vertebral fracture from osteoporosis (type 1 diabetes, certain medications, smoking), and neural tube defects (folic acid deficit, anti-convulsant medications, chlorine, influenza, maternal obesity). A range of comorbidities was identified for spinal disorders.

CONCLUSION

Many associated factors for common spinal disorders identified in this study are modifiable. The most common spinal disorders are co-morbid with general health conditions, but there is a lack of clarity in the literature differentiating which conditions are merely comorbid versus ones that are risk factors. Modifiable risk factors present opportunities for policy, research, and public health prevention efforts on both the individual patient and community levels. Further research into prevention interventions for spinal disorders is needed to address this gap in the literature.

Do Physical Activities Trigger Flare-ups During an Acute Low Back Pain Episode?: A Longitudinal Case-Crossover Feasibility Study

STUDY DESIGN

Prospective, longitudinal case-crossover study.

OBJECTIVE

The aim of this study was to determine whether physical activities trigger flare-ups of pain during the course of acute low back pain (LBP).

SUMMARY OF BACKGROUND DATA

.: There exist no evidence-based estimates for the transient risk of pain flare-ups associated with specific physical activities, during acute LBP.

METHODS

Participants with LBP of duration <3 months completed frequent, Internet-based serial assessments at both 3- and 7-day intervals for 6 weeks. At each assessment, participants reported whether they had engaged in specific physical activity exposures, or experienced stress or depression, during the past 24 hours. Participants also reported whether they were currently experiencing a LBP flare-up, defined as "a period of increased pain lasting at least 2 hours, when your pain intensity is distinctly worse than it has been recently." Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for associations between potential triggers during the past 24 hours, and the risk of LBP flare-ups, using conditional logistic regression.

RESULTS

Of 48 participants followed longitudinally, 30 participants had both case ("flare") and control periods and contributed data to the case-crossover analysis. There were 81 flare periods and 247 control periods, an average of 11 periods per participant. Prolonged sitting (>6 hours) was the only activity that was significantly associated with flare-ups(OR 4.4, 95% CI 2.0-9.7; P < 0.001). Having either stress or depression was also significantly associated with greater risk of flare-ups (OR 2.5, 95% CI 1.0-6.0; P = 0.04). In multivariable analyses, prolonged sitting (OR 4.2, 95% CI 1.9-9.1; P < 0.001), physical therapy (PT) (OR 0.4, 95% CI 0.1-1.0; P = 0.05), and stress/depression (OR 2.8, 95% CI 1.2-6.7; P = 0.02) were independently and significantly associated with LBP flare-up risk.

CONCLUSION

Among participants with acute LBP, prolonged sitting (>6 hours) and stress or depression triggered LBP flare-ups. PT was a deterrent of flare-ups.

LEVEL OF EVIDENCE

2.

Workplace interventions to improve sitting posture: A systematic review

PURPOSE

Evaluate the effectiveness of workplace interventions to improve sitting posture of workers that spend long periods of time seated at a visual display terminal.

METHODS

A systematic review of randomised controlled trials, non-randomised controlled trials and single-group intervention trials featuring workplace interventions with pre- and follow-up measurements of sitting posture was conducted (registered in PROSPERO, CRD#42015027648). Nine databases were searched for studies available between January 2005 and February 2016.

RESULTS

2519 articles were screened with 12 studies meeting the inclusion criteria. The included studies featured various ergonomic workplace interventions and comprised 4 randomised controlled trial (n=457), 2 non-randomised controlled trials (n=416) and 6 single-group intervention trials (n=328). Due to clinical and methodological heterogeneity, pooling of data was not completed and a narrative summary of findings was developed using the Grading of Recommendations Assessment Development and Evaluation (GRADE) framework. The evidence for four review outcomes was assessed with medium to large positive improvements obtained for the majority of studies investigating changes to gross sitting posture, whereas mixed findings were obtained for more specific local segment assessments of sitting posture. The overall evidence quality for all review outcomes were identified as either 'low' or 'very low'.

CONCLUSION

There is evidence which is limited in quality to indicate that ergonomic workplace interventions can improve gross sitting posture. More high quality research across a range of intervention types is required with longer follow-up durations and more advanced methods to assess sitting posture with greater frequency and less bias.

Low back pain among office workers in three Spanish-speaking countries: findings from the CUPID study

OBJECTIVES

To assess the differences in the prevalence and incidence of low back pain (LBP) and associated disability among office workers in Costa Rica, Nicaragua and Spain.

METHODS

Data were collected at baseline (n=947, 93% response) in November 2007 and at follow-up after 12 months (n=853, 90% response). Six outcome measures were examined: baseline prevalence of (1) LBP in the past 12 months, (2) LBP in the past month and (3) disabling LBP in the past month; and at follow-up: (4) incidence of new LBP in the past month, (5) new disabling LBP and (6) persistent LBP. Differences in prevalence by country were characterised by ORs with 95% CIs, before and after adjustment for covariates.

RESULTS

Prevalence of LBP in the past month among office employees in Costa Rica (46.0%) and Nicaragua (44.2%) was higher than in Spain (33.6%). Incidence of new LBP was 37.0% in Nicaragua (OR=2.49; 95% CI 1.57 to 3.95), 14.9% in Costa Rica (OR=0.74; 95% CI 0.41 to 1.34) and 19.0% in Spain (reference). Incidence of new disabling LBP was higher in Nicaragua (17.2%; OR=2.49; 95% CI 1.43 to 4.34) and Costa Rica (13.6%; OR=1.89; 95% CI 1.03 to 3.48) than Spain (7.7%), while persistence of LBP was higher only in Nicaragua.

CONCLUSIONS

Prevalence of LBP and disabling LBP was higher in Costa Rican and Nicaraguan office workers than in Spain, but the incidence was higher mainly in Nicaragua. Measured sociodemographic, job-related and health-related variables only partly explained the differences between countries, and further research is needed to explore reasons for the remaining differences.

A Survey on Low Back Pain Risk Factors in Steel Industry Workers in 2015

Study Design

This was a cross-sectional study.

Purpose

The aim of this study was to determine the prevalence of low back pain (LBP) and its association with individual factors and current job status among steel industry workers in Mashhad, Iran.

Overview of Literature

Several studies have been conducted on LBP and its related risk factors, some of which emphasized oc-cupational factors as the main etiology of LBP. Meanwhile, individual risk factors have been emphasized in other studies. Despite several published articles, there are still many unresolved, basic issues about developing LBP.

Methods

For this study, 358 male workers were selected by a random sampling method and divided into two groups: production workers (n=201) and administrative personnel (n=157). Data were collected using modified Nordic questionnaire and physical examination. Statistical analysis was performed to identify the correlation between individual factors and current job status with LBP.

Results

Despite the young age of participants and their short employment duration, the overall prevalence of LBP was high (32.4%) in this industry. The prevalence of non-specific LBP in production workers and administrative personnel was 26.8% and 21.0%, respectively. Disk herniation was observed in 10.4% of production workers and 6.3% of administrative personnel. Age, employment duration, body mass index and smoking status were similar in the two groups. There was no significant relationship between LBP and current job status; however, a significant relationship was found between prevalence of LBP with age, duration of employment, and leisure time physical activity (p<0.05).

Conclusions

We have not found any relationship between LBP and current occupational status suggesting that the effects of general health-related factors such as weight, age, leisure time physical activity, and duration of employment are more important than occupational factors in developing LBP.

Implications of sit-stand and active workstations to counteract the adverse effects of sedentary work: A comprehensive review

BACKGROUND

Sedentary work is associated with many adverse health outcomes, and sit-stand workstations in offices have emerged as a way to counteract sedentary work.

OBJECTIVE

This paper reviews the existing knowledge on sit-stand workstations, treadmill workstations and bicycle workstations.

METHODS

The inclusion/exclusion criteria were: 1) empirical research examining the effectiveness of sit-stand workstations in lab or field studies, 2) working adult population, 3) sit-stand workstation interventions where workers performed the same task from a seated or standing position, 4) outcomes measures of discomfort (comfort), performance, sit-stand behaviors, user satisfaction, kinematic and physiological measures. Search terms were: sit-stand, treadmill, bicycle, workstations, sedentary behavior, office ergonomics, and comfort.

RESULTS

Many studies considered productivity, comfort and physiological measures as important outcomes to assess the efficacy of sit-stand workstations and the experimental design was variable. Preliminary data suggests that some amount of standing during an 8-hour workday could be beneficial without compromising user comfort or productivity; however, there is very little data on the efficacy of treadmill and bicycle workstations.

CONCLUSIONS

Based on these preliminary data from 26 studies, conducting large scale randomized controlled trials with ergonomic training as their essential component is recommended to understand the benefits of sit-stand workstations for prevention of sedentary work.

Physiotherapists report improved understanding of and attitude toward the cognitive, psychological and social dimensions of chronic low back pain after Cognitive Functional Therapy training: a qualitative study

QUESTION

What are physiotherapists' perspectives on managing the cognitive, psychological and social dimensions of chronic low back pain after intensive biopsychosocial training?

DESIGN

Qualitative study design using semi-structured interviews to explore physiotherapists' perceptions of their identification and treatment of the biopsychosocial dimensions of chronic low back pain after intensive Cognitive Functional Therapy (CFT) training.

PARTICIPANTS

Thirteen qualified physiotherapists from four countries who had received specific CFT training. The training involved supervised implementation of CFT in clinical practice with patients. Interviews were audio-recorded and transcribed verbatim. An interpretive descriptive analysis was performed using a qualitative software package.

RESULTS

Four main themes emerged from the data: self-reported changes in understanding and attitudes; self-reported changes in professional practice; altered scope of practice; and increased confidence and satisfaction. Participants described increased understanding of the nature of pain, the role of patient beliefs, and a new appreciation of the therapeutic alliance. Changes in practice included use of new assessments, changes in communication, and adoption of a functional approach. Since undertaking CFT training, participants described a greater awareness of their role and scope of practice as clinicians in identifying and addressing these factors.

CONCLUSION

Physiotherapists expressed confidence in their capacity and skill set to manage the biopsychosocial dimensions of chronic low back pain after CFT training, and identified a clear role for including these skills within the physiotherapy profession. Despite this, further clinical trials are needed to justify the time and cost of training, so that intensive CFT training may be made more readily accessible to clinicians, which to date has not been the case. [Synnott A, O'Keeffe M, Bunzli S, Dankaerts W, O'Sullivan P, Robinson K, O'Sullivan K (2016) Physiotherapists report improved understanding of and attitude toward the cognitive, psychological and social dimensions of chronic low back pain after Cognitive Functional Therapy training: a qualitative study.Journal of Physiotherapy62: 215-221].

The Effect of Sitting on Stability Balls on Nonspecific Lower Back Pain, Disability, and Core Endurance: A Randomized Controlled Crossover Study

STUDY DESIGN

Experimental randomized crossover.

OBJECTIVE

The aim of the study was to determine whether sitting on a ball for 90 min/d instead of a chair has an effect on low back pain (LBP), low back disability, and/or core muscle endurance.

SUMMARY OF BACKGROUND DATA

LBP may result from prolonged sitting. It has been proposed that replacing chairs with stability balls can diminish LBP in those who sit for prolonged periods. Research on the topic is sparse and inconclusive.

METHODS

A total of 90 subjects (university students, staff, and faculty, ages 18-65, who sit ≥4 hr/d) were randomly assigned to the intervention or control group for the first part of the study. Baseline data were collected: Oswestry Disability Index, a numerical pain rating scale for LBP, and four core muscle endurance tests. For 8 weeks, the control group sat on their usual chair. The intervention group sat on stability balls 5 d/wk, increasing up to 90 min/d. Baseline measurements were repeated postintervention. After a washout period, subjects switched groups, and the procedures were repeated-70 completed participation in control group and 76 in intervention group.

RESULTS

There were no statistically significant differences for pain or disability in either group (P > 0.05). Changes in isometric trunk flexion (P = 0.001), nondominant side plank (P = 0.008), and Sorensen (P = 0.006) endurance scores were significant within the intervention group but not the control group. Between-group comparisons revealed a significant difference for isometric trunk flexion (P = 0.005) and Sorensen endurance times (P = 0.010). Analysis also showed that ball-sitting did not prevent an increase in LBP over the 8-week period.

CONCLUSION

Ball-sitting had no significant effects on LBP or associated disability, but did improve core endurance in the sagittal plane. Although ball-sitting may be useful as an adjunct treatment for LBP when core muscles are involved, clinicians should rely on other, evidence-based treatments for LBP.

Occupational sitting behaviour and its relationship with back pain - A pilot study

Nowadays, working in an office environment is ubiquitous. At the same time, progressively more people suffer from occupational musculoskeletal disorders. Therefore, the aim of this pilot study was to analyse the influence of back pain on sitting behaviour in the office environment. A textile pressure mat (64-sensor-matrix) placed on the seat pan was used to identify the adopted sitting positions of 20 office workers by means of random forest classification. Additionally, two standardised questionnaires (Korff, BPI) were used to assess short and long-term back pain in order to divide the subjects into two groups (with and without back pain). Independent t-test indicated that subjects who registered back pain within the last 24 h showed a clear trend towards a more static sitting behaviour. Therefore, the developed sensor system has successfully been introduced to characterise and compare sitting behaviour of subjects with and without back pain.

Risk factors for back pain in marines; a prospective cohort study

Background

It is recognised that back pain (BP) is a debilitating medical problem in the soldier community, which limits operational readiness as well as work ability. As such, identification of risk factors is a necessity for effective preventive actions, but also regarded as important from a safety perspective. The aim of this prospective cohort study was therefore to identify risk factors for back pain and BP limiting work ability in active duty marines within a 6 and 12-month period.

Methods

Demographic characteristics, health-related factors and occupational exposure information, as gathered from questionnaires, as well as clinical test of movement control among 137 Swedish marines were regressed with multivariable logistic regressions, and strength of associations was presented as odds ratio (OR) with 95 % confidence intervals (CI). BP within 6 and 12 months were used as primary outcomes, whereas BP limiting work ability within 6 and 12 months served as secondary outcomes.

Results

Previous BP and tall body height (≥1.86 m) emerged as risk factors for back pain within 6 months (OR 2.99, 95 % CI 1.22–7.30; OR 2.81, 95 % CI 1.16– 6.84, respectively), and 12 months (OR 6.75, 95 % CI 2.30–19.80; 2.75, 95 % CI 1.21–6.29, respectively). Previous BP was also identified as risk factor for BP limiting work ability within 12 months (OR 6.64, 95 % CI 1.78–24.78), and tall body height emerged as a risk within both six (OR 4.30, 95 % CI 1.31–14.13) and 12 months (OR 4.55, 95 % CI 1.53–13.57) from baseline.

Conclusions

Marines with a history of BP are at risk of further BP episodes, which, thus, emphasise the importance of early BP preventive actions. Tall body height also emerged as an important risk which may reflect that personal equipment and work tasks are not adapted for the tallest marines. While this should be considered when introducing new work equipment, further studies are warranted to clarify the underlying mechanism of this association.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-016-1172-y) contains supplementary material, which is available to authorized users.

Too much sitting and all-cause mortality: is there a causal link?

Background

Sedentary behaviours (time spent sitting, with low energy expenditure) are associated with deleterious health outcomes, including all-cause mortality. Whether this association can be considered causal has yet to be established.

Using systematic reviews and primary studies from those reviews, we drew upon Bradford Hill’s criteria to consider the likelihood that sedentary behaviour in epidemiological studies is likely to be causally related to all-cause (premature) mortality.

Methods

Searches for systematic reviews on sedentary behaviours and all-cause mortality yielded 386 records which, when judged against eligibility criteria, left eight reviews (addressing 17 primary studies) for analysis. Exposure measures included self-reported total sitting time, TV viewing time, and screen time. Studies included comparisons of a low-sedentary reference group with several higher sedentary categories, or compared the highest versus lowest sedentary behaviour groups. We employed four Bradford Hill criteria: strength of association, consistency, temporality, and dose–response. Evidence supporting causality at the level of each systematic review and primary study was judged using a traffic light system depicting green for causal evidence, amber for mixed or inconclusive evidence, and red for no evidence for causality (either evidence of no effect or no evidence reported).

Results

The eight systematic reviews showed evidence for consistency (7 green) and temporality (6 green), and some evidence for strength of association (4 green). There was no evidence for a dose–response relationship (5 red). Five reviews were rated green overall. Twelve (67 %) of the primary studies were rated green, with evidence for strength and temporality.

Conclusions

There is reasonable evidence for a likely causal relationship between sedentary behaviour and all-cause mortality based on the epidemiological criteria of strength of association, consistency of effect, and temporality.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-016-3307-3) contains supplementary material, which is available to authorized users.