Does sedentary behavior increase the risk of low back pain? A population-based co-twin study of Spanish twins

Screen-based sedentary behavior, physical activity, and the risk of chronic spinal pain: a cross-sectional and cohort study

BACKGROUND

Sedentary behavior (SB) is associated with chronic musculoskeletal pain, but limited evidence exists about its impact on chronic spinal pain (CSP).

AIM

This study aims to explore the relationship between SB, physical activity, and the risk of CSP.

DESIGN

Cross-sectional and cohort study design.

SETTING

United Kingdom (UK).

POPULATION

We included 481872 data collected between 2006 and 2010 for cross-sectional analysis and 45,096 data with the longest follow-up up to 2019 for longitudinal analysis of data from the UK.

METHODS

Screen-based SB was defined as self-reported television (TV) viewing time, computer usage time, and total screen time. CSP was characterized as self-reported neck/shoulder or back pain for more than 3 months.

RESULTS

Cross-sectional analyses suggested that screen-based SB is associated with a high risk of chronic neck/shoulder (OR [95%CI]=1.43 [1.31 to 1.57]) and back pain (OR [95%CI]=1.39 [1.28 to 1.52]). The longitudinal analysis showed that an increase of 1 h in daily screen-based SB was correlated with chronic back pain risk (RR [95% CI]=1.05 [1.03 to 1.07]). Replacing an equivalent amount of TV viewing time with 1 h of walking per day exhibited a connection with a lower potential for chronic neck/shoulder pain (4.82% reduction) and chronic back pain (5.26% reduction). Even replacing 10 min of TV viewing time with 10 min of physical activity demonstrated a similar trend.

CONCLUSIONS

Daily screen-based SB is associated with CSP, but a causal relationship cannot be established. Replacing sedentary TV time with 10 minutes of physical activity per day shows potential benefits for CSP.

CLINICAL REHABILITATION IMPACT

The public should be encouraged to reduce screen-based sedentary behavior and increase physical activity to mitigate the risk of chronic spinal pain.

Beneficial and harmful effects of physical activity on care-seeking for low back pain: the AUTBACK study

PURPOSE

People who seek more care for low back pain (LBP) tend to experience poorer recovery (e.g. higher pain and disability levels). Understanding the factors associated with care-seeking for LBP might improve patient outcomes and potentially alleviate the burden of LBP on global health systems. This study aimed to investigate the relationship between different intensities, volumes, and domains of physical activity and care-seeking behaviours, in people with a history of LBP.

METHODS

Longitudinal data from adult twins were drawn from the AUstralian Twin BACK study. The primary outcome was the total self-reported frequency (counts) of overall utilisation of care for LBP, over 1 year. Secondary outcomes were the utilisation of health services, and the utilisation of self-management strategies, for LBP (assessed as total frequency over 1 year). Explanatory variables were device-based measures of sedentary behaviour and moderate-to-vigorous intensity physical activity, and self-reported physical workload, and work, transport, household, and leisure domain physical activity, at baseline.

RESULTS

Data from 340 individuals were included. Median age was 56.4 years (IQR 44.9-62.3 years) and 73% of participants were female. Medium-to-high baseline volumes of sedentary behaviour were significantly associated with greater counts of overall care utilisation (IRR 1.60, 95%CI 1.04-2.44) and utilisation of self-management strategies (IRR 1.60, 95%CI 1.02-2.50) for LBP, over 1 year. Medium-to-high baseline volumes of household domain physical activity were significantly associated with greater counts of utilising self-management strategies for LBP over 1 year (IRR 1.62, 95%CI 1.04-2.53). No explanatory variables were associated with the utilisation of health services for LBP.

CONCLUSION

People who engage in higher baseline volumes of sedentary behaviour or physical activity in the household setting (e.g. housework, gardening, yard work, general household maintenance) utilise 1.6 times more care for LBP over 1 year. Findings suggest that higher volumes of these behaviours may be harmful for LBP. No intensities, volumes, or domains of physical activity demonstrated clear benefits for LBP. Where feasible, patients and clinicians should collaborate to screen and develop strategies to reduce engagement in sedentary behaviour or physical activity in the household setting. Contextual factors (e.g. patient symptom severity, sociocultural roles, occupational demands) should be considered when devising appropriate behaviour change strategies.

Prevalence of lower back pain and its associations with lifestyle behaviors among college students in Saudi Arabia

BACKGROUND

Lower back pain (LBP) is a common musculoskeletal disorder that may affect students' daily lives. Recent psychological research showed a relevant connection between LBP and multidimensional health. However, the association between LBP and lifestyle behavior has not been established, and improving knowledge in this area may help develop preventive strategies and optimize college students' quality of life.

METHODS

A cross-sectional study of 1420 college students in Saudi Arabia was conducted, and participants who attended Saudi Universities were recruited from May 2021 to November 2021. An established validated online survey assessed LBP, sleep quality, time spent sedentary (sedentary duration), health responsibility, physical activity, nutrition, spiritual growth, interpersonal relationships, and stress management. Generalized Linear Regression was used to assess the associations between LBP severity and lifestyle behaviors after controlling for covariates.

RESULTS

LBP was prevalent among college students from Saudi Arabia. Most of the sample were young (23.81 ± 6.02), and female (83.7%). There were significant differences between students with and without LBP regarding age, BMI, sex, marital status, pain severity, overall lifestyle behavior, health responsibility, physical activity, nutrition, stress management, and global sleep quality. After controlling for age, BMI, sex, and marital status, there were significant associations between pain severity and global sleep quality (ß=0.2, p < .001, CI: 16 to 0.24), and sedentary duration (ß=0.03, p = .01, CI:0.009 to 0.06).

CONCLUSIONS

This study helped define the prevalence of LBP in college students in Saudi Arabia and evaluated the association between LBP and lifestyle behaviors. The findings showed that students with higher levels of poor sleep quality or sedentary behavior had higher levels of pain. Promoting sleep quality and reducing sedentary behavior may help establish preventive strategies for LBP in college students.

Hole Matrix Mapping Model for Partitioned Sitting Surface Based on Human Body Pressure Distribution Matrix

(1) Objective: The objective of this study was to experimentally obtain the ideal pressure distribution model of buttock and thigh support for office workers in forward-leaning and upright sitting postures, reproduce the support provided by mesh materials with elastic materials, and propose an effective seat design scheme to improve the comfort of office workers. (2) Method: Based on the seven most popular mesh chairs on the market, pressure distribution experiments, and the fuzzy clustering algorithm, the relatively ideal body pressure distribution matrices were generated for office workers under two common sitting postures, and the corresponding partitioned sitting support surfaces were obtained. A prototype chair was created and validated by combining the ergonomics node coordinates and the physical properties of the materials. (3) Result: An ideal support model of four zones was constructed, and prototype pads were designed and produced according to this model. Subjects were recruited to test the ability of the prototypes to reproduce the ideal pressure distribution maps. (4) Conclusion: The four-zone ideal support model is capable of effectively representing the buttock and thigh support requirements in forward-leaning and upright sitting postures, and it is useful for the development of related products. Studying sitting postures and pressure values generated by different activities of office workers will help to refine the needs of office personnel and provide new ideas for the design of office chairs.

Short-term impact of COVID-19 pandemic on low back pain: data from the PAMPA Cohort, Brazil

BACKGROUND

To evaluate the short-term impact of COVID-19 pandemic on low back pain (LBP) outcomes in southern Brazil.

METHODS

Data from the PAMPA Cohort were analyzed. Adults were recruited between June and July 2020 in the Rio Grande do Sul state using online-based strategies. Participants responded a self-reported, online questionnaire on LBP with two timepoints: before (retrospectively) and during COVID-19 pandemic. We assessed LBP experience, LBP-related activity limitation (no/yes), and LBP intensity (0 to 10 [strongest pain]).

RESULTS

From a total sample of 2,321 respondents (mean age: 37.6 ± 13.5; 75.4% women), the prevalence of LBP did not change significantly from before (74.7% [95%CI 72.3; 76.9]) to the first months of pandemic (74.2% [95%CI 71.9; 76.3]). However, an increased pain levels (β: 0.40; 95%CI 0.22; 0.58) and a higher likelihood for activity limitation due to LBP was observed (PR 1.14; 95%CI 1.01; 1.29). Longitudinal analyzes showed that age, gender, BMI, chronic diseases, physical activity, and anxiety and depression symptoms, were associated with LBP in the first pandemic months.

CONCLUSION

Although the prevalence of LBP did not change at the first months of COVID-19 pandemic, LBP-induced impairment in daily activities and pain intensity was higher when compared to before the pandemic.

The association between sedentary behavior and low back pain in adults: a systematic review and meta-analysis of longitudinal studies

Background

Low back pain (LBP) is a common musculoskeletal problem globally. While spending a longer time in sedentary behaviors is linked to several health problems; the quantitative association between different amounts of sedentary time and LBP is still unknown. This study aims to systematically review studies that examined the association between sedentary behavior and LBP development and LBP-related outcomes.

Methods

This systematic review and meta-analysis retrieved journal articles published from inception to March 2020 and were obtained by searching bibliographical databases. We included longitudinal study designs, including adult (aged ≥18) individuals with nonspecific LBP, and reporting estimates of the association between sedentary behavior and LBP development and LBP-related outcomes (i.e., pain intensity and disability).

Results

Sixteen longitudinal studies with 100,002 participants were included in this review (eight studies included in quantitative syntheses with 83,111 participants). The results of meta-analyses showed that a sedentary time of 3-<6 (Odds ratio (OR) 0.95, 95% CI [0.85-1.07]), 6-8 (OR 0.95, 95% CI [0.88-1.02]), and >8 (OR 0.92, 95% CI [0.85-1.00]) hours per day (h/d) was not associated with LBP development. A sedentary time of ≥3 h/d was associated with poor LBP-related disability (OR 1.24, 95% CI [1.02-1.51]), but not with pain intensity.

Conclusion

A meta-analyses of longitudinal studies indicated that sedentary behavior of different durations was not associated with LBP development. However, the results showed that sedentary behavior ≥3 h/d was associated with worse LBP-related disability. These conclusions are tentative as the evidence was derived from mostly fair-quality studies using subjective measures of sedentary behavior.

Systematic review registration

PROSPERO (registration number CRD42018107078).

Association between sedentary behavior and low back pain; A systematic review and meta-analysis

Background: Sedentariness is a substantial risk for many chronic diseases. We aimed to investigate the correlation of sedentary behavior and its indicators with low back pain (LBP) among adults and children.

Methods: Original articles published up to April 28, 2020, using PubMed, Embase, Web of Science and Scopus were evaluated. Odds ratio (OR, 95% CI) was considered the overall effect size for desired associations.

Results: We reviewed 49 English articles with analytical observational study design, of which, 27 studies with cross sectional/survey design were retained in the meta-analysis. Among adults, sedentary lifestyle was a considerable risk factor for LBP (OR=1.24, 1.02-1.5); prolonged sitting time (OR=1.42, 1.09-1.85) and driving time (OR=2.03, 1.22-3.36) were the significant risk factors. Sedentary behavior was associated with LBP in office workers (OR=1.23). Moreover, excess weight (OR=1.35, 1.14-1.59) and smoking (OR=1.28, 1.03-1.60) were associated with LBP. Among children, sedentary lifestyle was a remarkable risk factor for LBP (OR=1.41, 1.24- 1.60); prolonged TV watching (OR=1.23, 1.08-1.41) and computer/mobile using and console playing time (OR=1.63, 1.36-1.95) were significant risk factors for LBP. Consumption of coffee, however, has yield conflicting results to be considered as a risk factor. Moreover, the researches on the correlation between sedentariness and high-intensity LBP are scarce and inconclusive.

Conclusion: Sedentary behavior, whether in work or leisure time, associates with a moderate increase in the risk of LBP in adults, children and adolescents.

Association of sedentary behavior and early engagement in physical activity with low back pain in adolescents: a cross-sectional epidemiological study

PURPOSE

To investigate the association of sedentary behavior and physical activity from childhood to adolescence with prevalence of low back pain in adolescents. In addition, we also explored whether sleep quality influences this association.

METHODS

This is a cross-sectional epidemiological study. Participants (aged 10-17 years) were recruited from public and private schools in Brazil. Sedentary behavior and previous and current engagement in physical activity were assessed through questionnaires. Low back pain and sleep quality were assessed by the Nordic questionnaire and Mini-Sleep Questionnaire, respectively. Sex, age, body mass index, abdominal obesity, socioeconomic status and sleep quality were used as potential confounders. Binary logistic regression models were used to generate values of odds ratio (OR) and 95% confidence intervals (95%CI).

RESULTS

A total of 1,001 (44,5% boys; n = 446) were included. Overall prevalence of low back pain was 18%, with higher rates among inactive and sedentary participants. Physical inactivity from childhood to adolescence in combination with high sedentary behavior doubled the likelihood of having low back pain (OR = 2.40 [95%CI: 1.38-4.18]), independent of potential confounders. Sleep quality attenuates, but not eliminates, this association (OR = 2.19 [95%CI: 1.25-3.84]).

CONCLUSION

Being inactive from childhood to adolescence in combination with high sedentary behavior is associated with low back pain in adolescents. Sleep quality seems to attenuate, but not eliminate, this association.

The Association Between Leisure-time Physical Activity, Sedentary Behavior, and Low Back Pain: A Cross-sectional Analysis in Primary Care Settings

STUDY DESIGN

Observational cross-sectional.

OBJECTIVE

To investigate the association between leisure-time physical activity (LTPA) and low back pain (LBP) in adults from primary care settings, and to explore how sedentary behavior influences this association.

SUMMARY OF BACKGROUND DATA

LTPA is inversely associated with LBP. However, there is no study investigating this association in primary care settings from a middle-income country. Moreover, the influence of sedentary behavior in this association is unknown.

METHODS

Cross-sectional analysis of an ongoing longitudinal study with adults from Bauru, Brazil (n = 557). Data on physical activity, sedentary behavior (sitting time), LBP, body mass index (BMI), and chronic diseases were assessed by face-to-face interviews, physical evaluation, and medical records. Binary logistic regression was used to test the association of LTPA with the presence of LBP. Sociodemographic, behavioral, and health variables were used as covariables in the multivariable models.

RESULTS

The fully adjusted model showed that active participants were 33% less likely to have LBP when compared with those insufficiently active (odds ratios [OR]: 0.67 [95% CI: 0.46-0.98]). A significant association was found for active participants who spent less than 3 h/day sitting (OR: 0.45 [95% CI: 0.23-0.89]) but not for those who spent 3 h/day or more in sedentary activities (OR: 0.78 [95% CI: 0.48-1.27]). An inverse association of LTPA with LBP was observed in obese participants (OR = 0.49 [95% CI: 0.25-0.94]), but not in those with normal BMI and overweight.

CONCLUSION

LTPA was inversely associated with the prevalence of LBP in adults from primary care. This association was influenced by sedentary behavior and BMI.Level of Evidence: 4.

Association Between Self-Reported Sedentary Behavior and Health-Related Quality of Life Among Multimorbidity Patients in Singapore

BACKGROUND

The study examined the association between sedentary behavior and self-rated health-related quality of life (HRQoL) in a sample of patients with multimorbidity in Singapore recruited from a primary care clinic.

METHODS

Sedentary behavior and physical activity were assessed with the International Physical Activity Questionnaire short form (IPAQ-SF). HRQoL was assessed with EuroQol-5 Dimension (EQ-5D) utility index, visual analogue scale (EQ-VAS) and its 5 subscales (Mobility, Self-care, Usual Activities, Pain/Discomfort, and Anxiety/Depression). Depression was assessed via Patient Health Questionnaire (PHQ-9). Logistic and linear regression analyses adjusting for the effect of physical activity, depression, and sociodemographic variables (i.e., age, gender, ethnicity, education) were conducted.

RESULTS

932 patients participated in the study (mean age:64.5±8.5 years, range: 35-80) and 55% were men. Results indicated that women were less likely to have sedentary behavior (≥7 hrs/day) than men. Results indicated sedentary behavior was associated with lower EQ-5D index scores, but not EQ-VAS scores. Participants who were sedentary for ≥7 hrs/day were more likely to endorse having problems with mobility, self-care, and usual activities, but not with pain/discomfort, nor anxiety/depression.

CONCLUSION

Sedentary behavior was associated with poorer HRQoL. There is a need for interventions and health promotions to reduce sedentary behavior in patients with multimorbidity.

Measurement Properties of the Sedentary Behavior Questionnaire in Patients with Chronic Nonspecific Low Back Pain

BACKGROUND

The Sedentary Behavior Questionnaire (SBQ) is a brief and easy instrument to measure time spent on sedentary activities; however, no study has investigated the reliability and validity of this questionnaire in people with chronic low back pain (LBP).

OBJECTIVE

To investigate the internal consistency, test-retest reliability, measurement error, construct validity, and interpretability of the SBQ against data derived from an accelerometer in patients with nonspecific chronic LBP.

STUDY DESIGN

Cross-sectional study.

SETTING

Outpatient physiotherapy clinic.

PATIENTS

Seventy-five patients aged between 18 and 60 years (mean age, 42 years old) with nonspecific chronic LBP were recruited for this study.

INTERVENTIONS

Not applicable.

METHODS

The Cronbach's α was calculated to investigate the internal consistency of the SBQ and the intraclass correlation coefficient (ICC) was calculated to investigate the reliability of the SBQ between two administrations separated by a 1-week interval. Measurement error was assessed calculating the SEM and minimal detectable change (MDC). Spearman correlation (r) was calculated to investigate the construct validity using hypothesis testing. Interpretability was investigated using ceiling and floor effects.

RESULTS

The Cronbach's α of the SBQ total score was 0.92, indicating homogeneity among the items of the instrument. The reliability of the SBQ was excellent (ICC > 0.75), without any evidence of ceiling and floor effects. Regarding measurement error, the total score of the SBQ showed an SEM and MDC of 109.8 minutes per day and 304.4 minutes per day, respectively. However, there were no correlations of the SBQ domains or the total score with the accelerometer-measured sedentary time (r < 0.25).

CONCLUSION

The SBQ is a reliable tool for quantifying time spent in sedentary activities of patients with chronic LBP. The SBQ showed poor construct validity compared to the accelerometer-measured sedentary time, which indicates that patients may underestimate their time spent in sedentary activities.

The effects of whole-body electromyostimulation (WB-EMS) in comparison to a multimodal treatment concept in patients with non-specific chronic back pain-A prospective clinical intervention study

Background

According to present guidelines, active exercise is one key component in the comprehensive treatment of nonspecific chronic back pain (NSCBP). Whole body electromyostimulation (WB-EMS) is a safe, and time-effective training method, that may be effective in NSCBP-patients.

Methods

In this prospective and controlled nonrandomized clinical study, two therapeutic approaches were compared. One group received 20 minutes WB-EMS per week. An active control group (ACG) received a multimodal therapy program. A third group included subjects without back pain. To all groups, the following measurement instruments were applied: Numeric Rating Scale (NRS), Oswestry Disability Index (ODI), North American Spine Society Instrument (NASS); SF 36 survey and measurements for muscular function and postural stability. In the EMS-group: T0: baseline; T1: at 6 weeks; T2: at 12 weeks and T3: at 24 weeks. In the ACG: T0 baseline and T1 after 4 weeks.

Results

In the intervention group, 128 patients with low back pain were enrolled, 85 in the WB-EMS group and 43 in the ACG. 34 subjects were allocated to the passive control group. The average age was 58.6 years (18–86 years). In the EMS group, the NRS (1–10) improved statistically and clinically significantly by 2 points. The ODI was reduced by 19.7 points. The NASS and most of the SF 36 items improved significantly. In the multimodal treatment group, only the muscular function improved slightly.

Conclusion

Our data support the hypothesis that WB-EMS is at least as effective as a multimodal treatment, which is often referred to as being the golden standard. Therefore WB-EMS may be an effective and, with 20 min./week training time, very time-efficient alternative to established multimodal treatment models.

Spinal pain is prospectively associated with cardiovascular risk factors in girls but not boys (CHAMPS study-DK)

PURPOSE

To examine the prospective associations between spinal pain exposures and risk factors for cardiovascular disease in children and explore the mediating role of health-related physical activity.

METHODS

Students were recruited from ten public primary schools. Each week from November 2008 to October 2010, parents reported spinal pain occurrences in their children via text messaging. Clustered cardiovascular risk was estimated with a composite score comprising fasting serum triglycerides, homeostasis assessment model-estimated insulin resistance (HOMA-IR), total to high-density lipoprotein cholesterol ratio, and systolic blood pressure. Additional outcomes were fasting serum insulin and glucose concentrations and body mass index categories. Associations were explored with multilevel mixed regression models and reported with beta coefficients (β) and percent difference scores. All models were adjusted for potential confounders.

RESULTS

Data from 1022 children (53% female) with mean ± SD age of 8.4 ± 1.4 years were included. Girls with spinal pain had greater clustered cardiovascular risk (β [95% CI]; percent difference [95% CI] = .41 [.02-.80]; 3.3% [.2-6.4%]) than those without spinal pain. Similar outcomes were observed for log insulin (percent difference [95% CI] = 3.4% [.6-6.2%]) and log HOMA-IR = (percent difference [95% CI] = 3.8% [.4-7.3%]). Remaining associations between spinal pain and cardiovascular risk in girls were nonsignificant. There were no associations between spinal pain and cardiovascular risk in boys. Moderate-to-vigorous-intensity physical activity did not appear to mediate this relationship.

CONCLUSION

These findings suggest a potentially important link between spinal pain and cardiovascular risk in girls that may be independent of health-related physical activity. These slides can be retrieved under Electronic Supplementary Material.

Is occupational or leisure physical activity associated with low back pain? Insights from a cross-sectional study of 1059 participants

BACKGROUND

Low back pain is a highly prevalent and disabling musculoskeletal disorder. Physical activity is widely used as a prevention strategy for numerous musculoskeletal disorders; however, there is still conflicting evidence as to whether physical activity is a protective or risk factor for low back pain or whether activity levels differ between people with and without low back pain.

OBJECTIVE

To investigate the association between low back pain and different types (occupational and leisure) and intensities (moderate and vigorous) of physical activity.

METHODS

This is cross-sectional observational study. We included in this study a total of 1059 individuals recruited from a Spanish twin registry with data available on low back pain.

OUTCOME

Self-reported leisure and occupational physical activity were the explanatory variables. The low back pain outcome used in this study was recurrent low back pain.

RESULTS

Our results indicate that leisure physical activity is associated with a lower prevalence of recurrent low back pain. In contrast, occupational physical activity, such as carrying, lifting heavy weight while inclined, awkward postures (e.g. bending, twisting, squatting, and kneeling) are associated with a higher prevalence of recurrent low back pain. There was no statistically significant association between other occupational physical activities, such as sitting or standing, and low back pain.

CONCLUSION

Leisure and occupational physical activity are likely to have an opposed impact on low back pain. While leisure physical activity appears to be protective, occupational physical activity appears to be harmful to low back pain. Future longitudinal studies should assist in formulating guidelines addressing specific types and intensity of physical activity aimed at effectively preventing low back pain.

The relationship between lumbopelvic flexibility and sitting posture in adult women

Clinical observations have suggested that limited hamstring flexibility may be associated with sagittal spinal curvatures in spine flexed postures. Thus, limited hamstring flexibility may be related to large amounts of spine flexion in "slumped" sitting postures which could contribute to low back pain and injury. The aim of this study was to determine if hamstring and pelvic flexibility are associated with flexed sitting postures using a backless office chair. Forty-one healthy female adults aged 18-69  years were recruited. Subjects performed the Sit-and-Reach test to determine maximum flexibility values and lumbar and pelvic angles were measured with accelerometers. Participants then completed a standardized typing task for a 10-minute sitting trial at an ergonomically adjusted workstation. The results showed no association between hamstring flexibility and seated lumbar spine and pelvic angles (p = 0.999, η2 = 0.000; p = 0.901, η2 = 0.006). Greater pelvic flexibility was associated with a more upright lumbar sitting posture (p = 0.023; η2 = 0.132) but with no specific pelvic sitting posture (p = 0.660; η2 = 0.005). Different movement strategies during the Sit-and-Reach test were detected: all participants moved through their lumbar spine; but only those with 'excellent' flexibility also used their pelvis. Individuals in the 'excellent' flexibility group were significantly shorter than those with 'poor' and 'good' flexibility (p = 0.020; η2 = 0.190). In conclusion, hamstring flexibility does not influence sitting posture but pelvic flexibility does. Other factors such as acetabulofemoral joint limitations, consciousness of posture, or the seat itself may also influence sitting posture. Different movement strategies as well as height appear to contribute to the Sit-and-Reach test which should be researched further.

Factors associated with musculoskeletal disorders and disability in elementary teachers: A cross-sectional study

The purpose of this study was to analyze factors associated with musculoskeletal disorders and disability in elementary teachers. This is a cross-sectional study from a representative sample of Brazilian elementary teachers (n = 530). Data were collected using a self-report questionnaire. Sociodemographic, work-related, and behavioural characteristics were the exposure variables. The outcomes were musculoskeletal symptoms, disability, and musculoskeletal disease. Musculoskeletal disease was used as an outcome, as well as an exposure variable when musculoskeletal symptoms and disability were the outcomes. Prevalence ratios (PR) were estimated by Poisson regression. Variables associated with musculoskeletal symptoms were: length of employment ≥20 years (PR = 1.41), perception of inappropriate infrastructure of schools (RP = 1.21), physical activity (PR = 0.80), and high stress (PR = 1.16) for upper limbs; high stress (PR = 1.23) and perception of inappropriate infrastructure of schools (RP = 1.16) for back/neck; common mental disorders (PR = 1.14 to 1.30), and musculoskeletal disease (PR = 1.19-1.62) for all regions of the body. Musculoskeletal disease (PR = 2.46 to 3.37) and perception of inappropriate infrastructure of schools (PR = 1.53 to 1.95) were associated to disability in all regions of the body. Length of employment >20 years was associated with disability in the upper limbs (PR = 2.06). Common mental disorders were associated with disability in the upper limbs (PR = 1.53) and back and neck (PR = 1.47) while sitting time >120 min/day was inversely associated with disability in the lower limbs (PR = 0.64). The predictors of musculoskeletal disease were length of employment ≥20 years (PR = 1.97), perception of inappropriate infrastructure of schools (PR = 1.57), strength and flexibility activities (PR = 1.66), TV viewing time ≥ 120 min (PR = 1.37), sports practice (PR = 0.39), and common mental disorders (PR = 1.39). Although the associations varied according to the outcome, common mental disorders, perception of inappropriate infrastructure of schools, high stress, and length of employment are variables to be considered in the prevention of musculoskeletal disorders in teachers. When analyzed as an exposure variable, musculoskeletal disease was the main predictor of musculoskeletal symptoms and disability.

Thoracic hyperkyphosis non invasively measured by general practitioners is associated with chronic low back pain: A cross-sectional study of 1364 subjects

OBJECTIVE

The aim of this study was to examine the association between trunk sagittal posture and nonspecific chronic low back pain (CLBP) by evaluating plumb-line distances in subjects recruited in an everyday clinical setting.

METHODS

Of the 1364 subjects recruited, 63.1% were female (mean age ± SD: 56.2 ± 16.8 years). Subjects were categorized into CLBP and control groups and were prospectively assessed over a 3-month period. They provided information about their daily activities and their history of CLBP. Prognostic factors were analysed using univariate and multivariate logistic regression analyses. A physical examination was performed to record demographic (i.e. age, height and weight) and pain characteristics, and the intensity of pain was assessed using a numerical visual analogue scale. Disability was assessed using the Roland-Morris Disability Questionnaire (RMDQ). A simple measure generally used for sagittal plane screening purposes during growth was also utilized.

RESULTS

Multivariate logistic regression analysis revealed that gender (OR = 1.70), RMDQ score (OR = 0.51) and thoracic hyperkyphosis (C7 + L3 at the plumb-line distance) (OR = 1.57) were associated with CLBP. The final regression model explained 85.6% (R² = 0.56; P < 0.001) of the variability.

CONCLUSIONS

General practitioners can clinically and easily assess trunk posture in subjects with low back pain to identify subjects at higher risk of CLBP.