Association between sitting and occupational LBP

The impact of breaking up sitting during simulated nightshifts on musculoskeletal pain: A randomised controlled trial

OBJECTIVES

Prolonged sitting is associated with an increased risk of musculoskeletal pain, especially in nightshift workers. However, research investigating effects of breaking up sitting on musculoskeletal pain during nightshifts is lacking. This study evaluated effects of prolonged sitting or breaking up sitting with short bouts of light-intensity physical activity on pain in healthy adults during simulated nightshifts.

METHODS

An in-laboratory randomised controlled trial was undertaken with 52 healthy adults completing five simulated nightshifts. Participants were randomised to prolonged sitting (Sit9; n = 26) or breaking up prolonged sitting (Break9; n = 26). Break9 group completed 3-min walking every 30 min during nightshifts, while Sit9 group remained seated. Musculoskeletal pain intensity and sensory/affective pain experiences were assessed. Linear mixed models examined pain within nights (pre-to post-shift) and across nights (pre-shift-night-1 to pre-shift-night-5).

RESULTS

Musculoskeletal pain intensity increased within nights for both Sit9 (mean change [95%CI] points: 0.14 [0.05, 0.24]) and Break9 (0.09 [0.001, 0.19], but not across nights (Sit9: -0.13 [-0.33, 0.08]; Break9: 0.07 [-0.14, 0.29]). Sensory-pain experience improved across nights for Sit9 (-3.08 [-4.72, -1.45]), but not within nights (0.77 [-0.004, 1.55]). There was no change in affective-pain experience in either group. Between-group difference was observed favouring Sit9 for improving sensory-pain across nights (β: 3.71 [1.42, 5.99]). No other between-group difference was observed.

CONCLUSION

Both prolonged sitting and breaking up sitting were associated with a within-night increase in musculoskeletal pain intensity. Compared to prolonged sitting, breaking up sitting did not induce benefits on pain in healthy adults working simulated nightshifts.

TRIAL REGISTRATION

ACTRN12619001516178.

A week-long field study of seated pelvis and lumbar spine kinematics during office work

The study objective was to quantify "natural" seated pelvis and lumbar spine kinematics over multiple days of work at individuals' workstations. Twenty participants completed five days of their usual office work while seated time was characterized from a thigh-worn activity monitor. Seated pelvic tilt and lumbar spine flexion-extension were measured from tri-axial accelerometers. Seated time accounted for approximately 90% of participants' workdays. Sitting was characterized by posterior pelvic tilt and lumbar flexion (43-79% of maximum flexion) with an average of 9 shifts and 13 fidgets every 15 min. No significant differences emerged by sex or between days indicating that a single representative day can capture baseline sitting responses in the field. Average field kinematics tended to agree with the laboratory-collected kinematics, but postural variability was larger in the field. These kinematic values could be useful for designing interventions aimed at reducing spine flexion and increasing spine movement in occupational sitting.

Traditional versus dynamic sitting: Lumbar spine kinematics and pain during computer work and activity guided tasks

Dynamic sitting may mitigate low back pain during prolonged seated work. The current study compared pelvis and lumbar spine kinematics, pain, and work productivity, in traditional and dynamic sitting. Sixteen participants completed three 20-min blocks of computer work and activity guided tasks in a traditional office chair or backless and multiaxial rotating seat pan while kinematics were measured from accelerometers on the low back. Pain ratings were recorded on a visual analogue scale every 10 min. Similar pelvis and lumbar kinematics emerged when performing computer work in traditional and dynamic sitting. Pelvis and lumbar sagittal and frontal plane shifts and fidgets were largest for dynamic sitting in the activity guided tasks. Buttocks pain was higher in dynamic sitting, but low back pain and work productivity were unaffected. Dynamic sitting increased spine movement during activity guided tasks, without negatively impacting lumbar kinematics, low back pain, or productivity during seated computer work.

The relationship between core endurance, physical activity level and balance in office workers

Objectives. The aim of this study was to evaluate the relationship between core endurance tests and physical activity level, balance, ergonomics and pain in office workers. Methods. The study included 57 office workers who had been employed for at least 1 year. Core endurance was assessed using McGill core endurance tests. Physical activity, balance, pain and ergonomic risks were evaluated with the international physical activity questionnaire (IPAQ), timed up and go (TUG), visual analog scale (VAS) and rapid office strain assessment (ROSA), respectively. Results. A significant correlation was found between balance and static core endurance tests. However, no significant correlation was found between ergonomics and physical activity level and core endurance tests except for trunk extension and prone bridge tests. In addition, there was a significant difference in core endurance tests for patients with and without regular exercise habits. Waist circumference and hip circumference measurements were found to be significantly negatively associated with static core tests. Conclusion. Core endurance was found to be associated with exercise habits, balance, hip and waist circumference and ergonomics in office workers. Improving core endurance may be beneficial for preventing musculoskeletal risks in office workers.

Exploring the impact of occupational factors on low back pain in ride-sharing motorbike drivers in Bangladesh: A comprehensive cross-sectional analysis

Objective

Low back pain (LBP) is a major global public health issue, prevalent among various occupational groups worldwide. However, existing studies have predominantly focused on sedentary workers in developed nations, leaving a gap in understanding LBP prevalence and associated factors among occupational cohorts in low- and middle-income countries like Bangladesh. This study aimed to determine the prevalence and occupational factors contributing to LBP among ride-sharing motorbike drivers (RSMD) in Bangladesh.

Methods

A cross-sectional study was conducted in Dhaka city from May 20 to August 08, 2023. Data were collected from Bangladeshi adult RSMD using a paper-based questionnaire developed by Eriksen et al. Chi-square or Fisher's Exact tests compared categorical variables with and without LBP, and multiple logistic regression analyses were performed with LBP as the dependent variable and various predictors to compute adjusted odds ratios with a 95% confidence interval.

Results

The one-month prevalence of LBP was 58.8%. Regression analysis revealed elevated adjusted odds of experiencing LBP among participants with hypertension, those using multiple ride-sharing operators, commuter and older bike users, and non-users of riding kits. Additionally, increased adjusted odds of LBP were observed among participants of higher age, higher body mass index, and those covering longer distances per week.

Conclusion

This study underscores a significantly higher prevalence of LBP among RSMD in Bangladesh, with occupational factors strongly predicting LBP. Implementing strategies such as regular physical exercise, weight reduction, using sports and newer motorbikes, and reducing working hours per week may help mitigate the prevalence of LBP within this cohort.

Evaluation of low back pain status and affecting factors in drivers in Turkey: A cross-sectional study1

BACKGROUND

Low back pain (LBP) is a common public health problem resulting in workforce loss.

OBJECTIVE

This study aims to evaluate the LBP status and its affecting factors among drivers in a city in southeast Turkey.

METHODS

This cross-sectional questionnaire survey study was conducted among 323 drivers. The chi-square test and logistic regression analysis were used to analyze the data.

RESULTS

The mean age of the drivers was 41.7±11.5 years (min: 19, max: 70), and 83.9% were married, and all were men. LBP was found in 59.4% of drivers. It was significantly higher in drivers with poor socioeconomic status, dissatisfied with their life, having a chronic illness, physically inactive, having sleep disorders, exposed to bad road conditions, prolonged vibration, high physical- psychological workload, and a family history of LBP (p <  0.05). There was no significant association between age, education level, and BMI with LBP (p >  0.05).

CONCLUSION

There is limited study on this subject in Turkey. Further studies can raise awareness about this issue and create an educational plan.

Characterization of workers or population percentage affected by low-back pain (LPB), sciatica and herniated disc due to whole-body vibrations (WBV)

Whole-body vibrations have several harmful effects on the population's health. The most suitable way to characterize the vibrations is to use the daily vibration exposure A (8) and Vibration Dose Value as specified in Directive 2002/44/EC. Therefore, based on the existing literature, we propose Probit equations that allow us to relate the population percentage affected by the vibration effects (low-back pain, sciatica, and herniated disc) with the A (8) and the Vibration Dose Value. It is worth noting that there is a good correlation between the experimental data and the expressions obtained, especially for low-back pain and herniated discs. Once the expressions have been validated, we analyze the limit values given in the aforementioned legislation, showing that the percentage of the affected population is significant for them. Therefore, this study also proposes new limits based on their own definitions, which are more in line with the results shown in the bibliography.

The effect of exercise therapy as a tool for preventing and treating musculoskeletal disorders among school-aged children: a randomised controlled trial

BACKGROUND

Children spend a lot of time in school, and there are many ergonomic hazards and postural malalignments that put children at greater risk of developing musculoskeletal disorders (MSDs). This study aimed to investigate the effect of exercise therapy on preventing and treating musculoskeletal disorders among school-aged children.

METHOD

This randomised controlled trial included 212 (121 boys and 91 girls) school-aged children aged 13-15 years assigned to treatment (n = 106) and prevention (n = 106) groups, where the treatment group contained individuals with MSDs and prevention group contained individuals without MSDs. In each group, half of the individuals received exercise therapy (50 min per session, four times per week, for an 8-week), and others continued their daily lives. MSDs and physical activity were assessed by the Teen Nordic Musculoskeletal Screening Questionnaire and the International Physical Activity Questionnaire-Short Form, respectively, at baseline and after the experimental protocol.

RESULTS

There was a statistically significant reduction in the frequency of MSDs in the treatment group and occurring MSDs in the prevention group (P ≤ .05). Also, there was significant improvement in all variables of walking, moderate physical activity, vigorous physical activity, and total in intervention groups spatially in students who received exercise therapy (P ≤ .05).

CONCLUSIONS

This study demonstrated the effectiveness of exercise therapy in reducing and preventing MSDs and improving physical activity levels among school-aged children aged 13-15 years.

TRIAL REGISTRATIONS

Ethical Committee of Shahrekord University (IR.SKU.REC.1401.022) (registration date: 31/05/2022). Clinical Trail Registration (IRCT20220705055375N1), (registration date: 29/07/2022).

Assessing the Preservation of Lumbar Lordotic Curvature in Everyday Sitting Conditions Assessed with an Inertial Measurement System

Background/Objectives: Lumbar lordotic curvature (LLC), closely associated with low back pain (LBP) when decreased, is infrequently assessed in clinical settings due to the spatiotemporal limitations of radiographic methods. To overcome these constraints, this study used an inertial measurement system to compare the magnitude and maintenance of LLC across various sitting conditions, categorized into three aspects: verbal instructions, chair type, and desk task types. Methods: Twenty-nine healthy participants were instructed to sit for 3 min with two wireless sensors placed on the 12th thoracic vertebra and the 2nd sacral vertebra. The lumbar lordotic angle (LLA) was measured using relative angles for the mediolateral axis and comparisons were made within each sitting category. Results: The maintenance of LLA (LLAdev) was significantly smaller when participants were instructed to sit upright (-3.7 ± 3.9°) compared to that of their habitual sitting posture (-1.2 ± 2.4°) (p = 0.001), while the magnitude of LLA (LLAavg) was significantly larger with an upright sitting posture (p = 0.001). LLAdev was significantly larger when using an office chair (-0.4 ± 1.1°) than when using a stool (-3.2 ± 7.1°) (p = 0.033), and LLAavg was also significantly larger with the office chair (p < 0.001). Among the desk tasks, LLAavg was largest during keyboard tasks (p < 0.001), followed by mouse and writing tasks; LLAdev showed a similar trend without statistical significance (keyboard, -1.2 ± 3.0°; mouse, -1.8 ± 2.2°; writing, -2.9 ± 3.1°) (p = 0.067). Conclusions: Our findings suggest that strategies including the use of an office chair and preference for computer work may help preserve LLC, whereas in the case of cueing, repetition may be necessary.

Pain and self-pressure relief in adolescents with cerebral palsy

Adolescents with CP classified as Gross Motor Functional Classification System Level V attend school up to 8 h daily with limited ability to self-reposition. Despite pain reported within this population, perceived pain and self-pressure relief during prolonged classroom sitting is unknown. A case series design was used with a convenience sample of six students (13-18 years) with CP. Pain assessments were taken every 30 min for 5 h. Self-relief assessments using the SensiMATTM were recorded while students were in their wheelchairs. One student self-reported pain and three students proxy reported pain movements. All students had unrelieved pressure or did not self-relieve pressure for at least 1.5 consecutive hours. Four students increased their self-pressure relief movements after 3.5 h. This study provided preliminary data regarding perceived pain and self-pressure relief during prolonged sitting and demonstrated that the SensiMATTM can capture pressure relief movements in sitting of students with severe CP. Although there was no trend of reported pain, students may either be moving enough, as demonstrated by recorded pressure relief movements, to independently relieve pressure and pain, or current pain assessments may not be sensitive enough for those with the most severe disabilities.

Factors affecting functional disability in patients with non-specific chronic low back pain: a cross-sectional study

Background

Knowledge about factors affecting functional disability in patients with non-specific chronic low back pain (NSCLBP) is helpful in guiding treatment, but there has been little systematic research on this topic. This study aimed to identify independent factors contributing to functional disability in NSCLBP patients especially the impact of sagittal parameters and body postures in work, learning, and daily life.

Methods

Sociodemographic data, sagittal parameters, Oswestry Disability Index (ODI), Numeric Rating Scale (NRS), and 36-item Short Form Health Survey (SF-36) of NSCLBP patients were collected. Patients were divided into a low-functional disability group (ODI ≤ 20) and a high-functional disability group (ODI > 20), and the ODI was converted to ranked ODI (RODI) accordingly. Sociodemographic data, sagittal parameters, NRS, and SF-36 were compared by univariate analysis between both groups. A correlation analysis of the aforementioned factors with the RODI was conducted. The sociodemographic data and sagittal parameters related to the RODI were analyzed by logistic regression to select potential RODI-associated factors. The level of significance was set at P < 0.05.

Results

Age, educational background, daily main posture while working or learning (DMPWL), daily standing time while working or learning (DSTTWL), daily sitting time while resting (DSITR), sacral slope-pelvic tilt (SS-PT), spinosacral angle (SSA), NRS, and SF-36 (except mental health, MH) were different between the two groups (P < 0.05). Correlation analysis showed that they were related to the RODI (P < 0.05). The logistic regression analysis indicated that the regression coefficients of a college degree, postgraduate diploma, DSITR, and SSA were (B = -0.197; P = 0.003), (B = -0.211; P = 0.006), (B = -0.139; P = 0.039), and (B = -0.207; P = 0.001), respectively, and the odds ratio (OR) and 95% confidence interval (CI) were 0.489 (0.308; 0.778), 0.299 (0.125; 0.711), 0.875 (0.772; 0.993), and 0.953 (0.925; 0.981), respectively.

Conclusion

Educational background, DSITR, and SSA are independent factors affecting functional disability in NSCLBP patients. NSCLBP patients with a lower educational background, shorter DSITR, or smaller SSA should be taken into account in clinical practice and therapeutic choices. Extending sitting time for rest and the avoidance of a forward-leaning standing position are beneficial for reducing functional disability in NSCLBP.

Impact of home quarantine on physical fitness of school-aged children in Xi'an during COVID-19 lockdown: a cross-sectional study

BACKGROUND

The emergence of the COVID-19 pandemic has sparked unprecedented global challenges. This study intends to investigate changes in the physical fitness of students aged 6-22 during the COVID-19 pandemic and to assess how the pandemic lockdown period affected these markers.

METHODS

According to the National Student Physical Health Standard, a stratified cluster sampling method was used to evaluate the body shape, body function, and physical fitness of children and adolescents (n = 8092) in Xi'an from 2019 to 2021. This study uses SPSS 26.0 (IBM, Chicago, IL, USA) for data statistics and analysis. The connection between physical fitness and years was measured using the one-variable analysis in the general linear model (GLM). Independent t-tests were used to determine the sex (male/female) and area (urban/rural) differences.

RESULTS

During the lockdown period, Body Mass Index (BMI) and flexibility showed an upward trend, while aerobic, strength, speed, and endurance showed a downward trend. In addition to the BMI of middle and high school students, almost all indicators show significant sex differences. There are urban-rural differences in some indicators, such as chin-ups.

CONCLUSION

During the pandemic of COVID-19, the physical fitness of children and adolescents in Xi'an did not change significantly, and there were slight differences among different grades. During the pandemic lockdown period, lifestyle changes and reduced outdoor activities for children and adolescents may be the reasons for the changing trend of various indicators.

Efficacy of Core Muscle Exercise Combined with Interferential Therapy in Alleviating Chronic Low Back Pain in High-Performance Fighter Pilots: A Randomized Controlled Trial

BACKGROUND

Chronic low back pain (LBP) related to flight is a prevalent health issue in military aviation, impacting pilots. The objective of this investigation was to ascertain if the application of core muscle training in conjunction with interferential current (IFC) therapy results in a reduction in pain severity and associated disability, consequently enhancing core muscle functionality in Chinese Air Force high-performance fighter pilots experiencing chronic LBP.

METHODS

Fifty-three fighter pilots with chronic LBP were randomized into 3 groups: a core muscle exercise combined with IFC group (CG, n = 19), a core muscle exercise group (EG, n = 19), and an IFC group (IG, n = 15). The three groups underwent therapeutic intervention 5 times a week for 12 weeks. The primary outcomes were pain intensity, Oswestry Disability Index (ODI) score and SF-12 health-related quality of life (PCS and MCS) score. Secondary outcomes included evaluations of trunk muscle strength, endurance, and range of motion (ROM) during medial/lateral rotation to assess muscle functionality. Measurements were obtained both before and after the implementation of the intervention therapy.

RESULTS

After 12 weeks of intervention therapy, all the health condition parameters significantly improved among the three groups. However, the CG had a significant improvement in pain intensity compared to the EG (MD = - 0.84 scores; 95% CI = - 1.54 to - 0.15; p = 0.013) and the IG (MD = - 1.22 scores; 95% CI = - 1.96 to - 0.48; p = 0.000). Additionally, the CG led to greater conservation of ODI and improved SF-12 PCS scores than did the IG (p < 0.05). Finally, compared with those at baseline, the core muscle function parameters in the CG and EG improved significantly at the end of the study, but no statistically significant differences were observed between the two groups (p > 0.05).

CONCLUSION

Among participants with chronic LBP, three intervention therapies appear effective in reducing pain, diminishing disability, and enhancing quality of life. Also, combined therapy significantly improved pain and disability compared to the other two monotherapies; moreover, combined therapy and core muscle exercise provided similar benefits in terms of core muscle function after 12 weeks of intervention therapy.

Socioeconomic variation in the prevalence of pain by anatomical sites among middle-aged and older adults in India: a cross-sectional study

BACKGROUND

Pain is a significant global public health concern, particularly among individuals aged 45 and above. Its impact on the overall lifestyle of the individuals varies depending on the affected anatomical parts. Despite its widespread impact, there is limited awareness of the attributes of pain, making effective pain management challenging, particularly in India. This study aims to estimate the prevalence and variation in pain in different anatomical sites among middle-aged and older adults in India.

METHODS

A cross-sectional design was employed, utilising data from the first wave of the Longitudinal Aging Study in India (LASI), 2017-2018. The age-sex adjusted prevalence of pain by anatomical sites (the back, joints, and ankles) was estimated using a multivariate logistic regression model.

RESULTS

47% of individuals aged 45 years and above reported joint pain, 31% reported back pain and 20% suffered from ankle or foot pain. The prevalence of pain at all the anatomical sites increased with age and was reported higher among females. Relative to respondents aged 45-59 years, those aged 75 years and older exhibited a 41% higher likelihood of experiencing back pain (AOR: 1.41, 95% CI: 1.19-1.67), a 67% higher likelihood of joint pain (AOR: 1.67, 95% CI: 1.49-1.89), and a 32% higher likelihood of ankle/foot pain (AOR: 1.32, 95% CI: 1.16-1.50). In comparison to males, females had a 56% higher likelihood of encountering back pain (AOR: 1.56, 95% CI: 1.40-1.74), a 38% higher likelihood of joint pain (AOR: 1.38, 95% CI: 1.27-1.50), and a 35% higher likelihood of ankle/foot pain (AOR: 1.35, 95% CI: 1.17-1.57). We also found significant regional variations in pain prevalence, with higher rates in the mountainous regions of India.

CONCLUSION

This research highlights the high burden of pain in major anatomical sites among middle-aged and older adults in India and emphasises the need for increased awareness and effective pain management strategies.

The Effect of an Active Break Intervention on Nonspecific Low Back Pain and Musculoskeletal Discomfort during Prolonged Sitting among Young People-Protocol for a Randomized Controlled Trial

BACKGROUND

The most recent evidence has shown that the pandemic of COVID-19 caused an increasing problem with spinal pain in the population of teenagers and young adults. This may be explained by prolonged sitting times in flexed positions with electronic devices. Positions maintained for a prolonged time cause overloading of soft tissue and discogenic symptoms. This study aims to evaluate the effectiveness of the active break program in reducing musculoskeletal discomfort and LBP (low back pain) among young people.

METHODS

This will be a randomized controlled study. The participants will be recruited from Bachelor's course students of the Physical Education Department aged 18-25 years. The participants will be assigned to an experimental group (with an active break) and a control group. The group with an active break with lumbar and hip extension exercises will be recommended to take a break for every 30 min of sitting. The control group will receive self-care recommendations. The primary outcomes will be pain intensity (Visual Analogue Scale), disability index (Oswestry Disability Index), and perceived musculoskeletal discomfort during prolonged sitting (Borg scale), assessed at baseline and after the intervention, and the Global Perceived Effect, only assessed after the 12-week intervention. The secondary outcome will be a Post-Intervention Questionnaire (a 5-item self-completed questionnaire), only assessed after the 12-week intervention.

RESULTS

Our main research outcome-exercise protocols and interventions-will lead to the development of recommendations and protocols for the LBP population. It is important to determine the effect of interventions that are feasible and effective in addressing LBP and perceived musculoskeletal discomfort in young people.

CONCLUSIONS

This is the first study examining the effect of active breaks with proposed lumbar and hip extension exercises on reducing or decreasing LBP in students based on a search of the literature. Exercises and recommendations will be the basis for developing proprietary preventative and therapeutic programs, which will be implemented in selected educational institutions.

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.

Āsana for Back, Hips and Legs to Prevent Musculoskeletal Disorders among Dental Professionals: In-Office Yóga Protocol

Dental professionals are exposed to significant unavoidable physical stress, and theoretical ergonomic recommendations for a sitting workplace are inapplicable in many dental activities. Work-related musculoskeletal disorders (WMSDs) represent a serious health problem among dental professionals (prevalence: 64-93%), showing involvement of 34-60% for the low back and 15-25% for the hips. Muscle stress; prolonged sitting; forward bending and twisting of the torso and head; unbalanced working postures with asymmetrical weight on the hips and uneven shoulders; and others are inevitable for dental professionals. Therefore, the approach for the prevention and treatment of WMSDs must be therapeutic and compensatory. This project was conceived to provide a Yoga protocol for dental professionals to prevent or treat WMSDs from a preventive medicine perspective, and it would represent a Yoga-based guideline for the self-cure and prevention of musculoskeletal problems.

METHODS

Specific Yoga positions (āsana, such as Virāsana, Virabhadrāsana, Garudāsana, Utkatāsana, Trikonāsana, Anuvittāsana, Chakrāsana, Uttanāsana, Pashimottanāsana) have been selected, elaborated on and adapted to be practiced in a dental office using a dental stool or the dental office walls or a dental unit chair. The protocol is specifically devised for dental professionals (dentists, dental hygienists and dental assistants) and targeted for the low back, hips and legs (including knees and ankles). The protocol includes Visranta Karaka Sthiti (supported positions) in sitting (Upavistha Sthiti) and standing (Utthistha Sthiti) positions, twisting/torsions (Parivrtta), flexions/forward bend positions (Pashima) and extensions/arching (Purva) for musculo-articular system decompression and mobilization.

RESULTS

Over 60 Yogāsana-specifically ideated for back detensioning and mobilization, lumbar lordosis restoration, trunk side elongation, hip release and leg stretches and decontraction-are shown and described. The paper provides a meticulous description for each position, including the detailed movement, recommendations and mistakes to avoid, and the breathing pattern (breath control) in all the breath-driven movements (āsana in vinyāsa). An exhaustive analysis of posture-related disorders affecting the lower body among dental professionals is reported, including low-back pain, hip pain and disorders, piriformis syndrome and quadratus femoris dysfunction (gluteal pain), iliopsoas syndrome, multifidus disorders, femoroacetabular and ischiofemoral impingement, spinopelvic mobility, lumbopelvic rhythm, impairment syndromes, lower crossed syndrome, leg pain, knee pain and ankle disorders.

CONCLUSIONS

A detailed guideline of āsana for low-back decompression, hip joint destress, piriformis and gluteal muscle release, lumbar lordosis recovery and a spinopelvic mobility increase has been elaborated on. The designed Yogāsana protocol represents a powerful tool for dental professionals to provide relief to retracted stiff muscles and unbalanced musculoskeletal structures in the lower body.

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.

Low Back Pain in Resident Doctors with Standardized Training in China: A Cross-Sectional Study

Background

Low back pain (LBP) is a prevalent occupational disease with high morbidity among healthcare workers. Since the implementation of standardized residency training in China in 2015, the training intensity has significantly increased, which may lead to a higher incidence of LBP. However, epidemiological studies on LBP among resident doctors with standardized training remain scarce.

Objective

To investigate the prevalence and associated factors of LBP among resident doctors with standardized training in a tertiary hospital in China.

Methods

A cross-sectional study was conducted using self-administered questionnaires to collect information on demographics, lifestyle factors, work-related factors, and LBP from 345 resident doctors. Descriptive statistics were used to analyze the prevalence of LBP. Logistic regression analysis was performed to identify factors associated with LBP.

Results

Among 345 participants, the 1-year prevalence of LBP was 75.9%. Multivariable analysis revealed that physical exercise, weekly working hours, and prolonged sitting were independent risk factors for LBP.

Conclusion

The prevalence of LBP among resident doctors was high. Promoting physical exercise, controlling working hours, and improving sitting posture may help prevent LBP. The study was limited by its cross-sectional design and self-reported data. Future studies should use longitudinal designs, objective measures, and larger and more representative samples to further explore the epidemiology and etiology of LBP among resident doctors with standardized training.

Impact of 10-Min Daily Yoga Exercises on Physical and Mental Discomfort of Home-Office Workers During COVID-19

OBJECTIVE

Evaluate the effects of 10 min/day of yoga for 1 month on musculoskeletal discomfort and mood disturbance of home-office workers.

BACKGROUND

The COVID-19 pandemic forced many people to switch to teleworking. The abrupt change from an office setting to an improvised home-office may negatively affect the musculoskeletal and emotional health of workers. By providing mental and physical exercises, yoga may be effective in reducing adverse effects.

METHOD

Fifty-four participants (42 women, 12 men) followed a 1-month yoga program, while 40 participants (26 women, 14 men) continued with their common work routine. The Cornell Musculoskeletal Discomfort Questionnaire was used to evaluate severity, interference with work and frequency of pain, and to obtain a total discomfort score for 25 body areas. Mood disturbance was evaluated with the Profile of Mood States questionnaire. Both groups completed both questionnaires, before and after the experimentation period.

RESULTS

After 1 month, for the yoga group only, significant reductions were observed in the discomfort of eyes, head, neck, upper and lower back, right wrist, and hips/buttocks, as well as reductions in discomfort severity, frequency and interference for the neck, upper and lower back. Total mood disturbance was also significantly reduced for the yoga group only. No favorable changes occurred for the control group.

CONCLUSION

The yoga intervention program appears to reduce musculoskeletal discomfort and mood disturbance of home-office workers.

APPLICATION

Sedentary workers may benefit from 10 min/day of yoga during the workday to attenuate potential physical and emotional discomfort during the current pandemic and beyond.

Greater number of weekly stairs climbed is associated with lower low back pain prevalence among female but not male physical therapists

INTRODUCTION

Certain cardiovascular health benefits of stair climbing are now widely accepted, but no prior studies have as yet been found linking the quantity of stairs climbed to low back pain (LBP) morbidity. Low back pain is a common musculoskeletal impairment, and research has begun to show an association between LBP and gluteus maximus (GM) weakness. With stair climbing being the activity which most activates GM, the aim of the present research was to assess the relationship between stair ambulation and LBP prevalence. The hypothesis of this cross-sectional study was that individuals with LBP would report a significantly lower numbers of stair flights climbed compared with individuals without LBP.

METHODS

A survey tool was developed and distributed via email to a convenience sample of orthopedic physical therapists. Survey items included information regarding medical history, physical activity, workplace, and LBP factors, using a one-year prevalence period.

RESULTS

A total of 363 respondents took the survey and, after application of exclusion criteria, 248 records remained in our final sample. When analyzing all genders together, non LBP (NLBP) respondents reported a mean of 51.62 flights climbed per week; and LBP respondents reported 37.82 flights climbed per week, with P = 0.077. When males and females were analyzed separately, a statistically significant difference in mean number of flights of stairs climbed was found among female respondents (61.51 flights climbed for NLBP and 35.61 flights climbed for LBP females; P = 0.031). When analyzed based on chronicity of LBP, an even stronger association between stairs climbed and LBP prevalence was found for female respondents with acute LBP (P = 0.009).

CONCLUSIONS

More weekly stairs climbed was associated with a lower LBP prevalence among females, especially with respect to acute LBP. Randomized, longitudinal research is, however, required to confirm a relationship between stair climbing and LBP.

A multicomponent intervention to reduce daily sitting time in office workers: the SMART Work & Life three-arm cluster RCT

Background

Office workers spend 70-85% of their time at work sitting. High levels of sitting have been linked to poor physiological and psychological health. Evidence shows the need for fully powered randomised controlled trials, with long-term follow-up, to test the effectiveness of interventions to reduce sitting time.

Objective

Our objective was to test the clinical effectiveness and cost-effectiveness of the SMART Work & Life intervention, delivered with and without a height-adjustable workstation, compared with usual practice at 12-month follow-up.

Design

A three-arm cluster randomised controlled trial.

Setting

Councils in England.

Participants

Office workers.

Intervention

SMART Work & Life is a multicomponent intervention that includes behaviour change strategies, delivered by workplace champions. Clusters were randomised to (1) the SMART Work & Life intervention, (2) the SMART Work & Life intervention with a height-adjustable workstation (i.e. SMART Work & Life plus desk) or (3) a control group (i.e. usual practice). Outcome measures were assessed at baseline and at 3 and 12 months.

Main outcome measures

The primary outcome was device-assessed daily sitting time compared with usual practice at 12 months. Secondary outcomes included sitting, standing, stepping time, physical activity, adiposity, blood pressure, biochemical measures, musculoskeletal issues, psychosocial variables, work-related health, diet and sleep. Cost-effectiveness and process evaluation data were collected.

Results

A total of 78 clusters (756 participants) were randomised [control, 26 clusters (n = 267); SMART Work & Life only, 27 clusters (n = 249); SMART Work & Life plus desk, 25 clusters (n = 240)]. At 12 months, significant differences between groups were found in daily sitting time, with participants in the SMART Work & Life-only and SMART Work & Life plus desk arms sitting 22.2 minutes per day (97.5% confidence interval -38.8 to -5.7 minutes/day; p = 0.003) and 63.7 minutes per day (97.5% confidence interval -80.0 to -47.4 minutes/day; p < 0.001), respectively, less than the control group. Participants in the SMART Work & Life plus desk arm sat 41.7 minutes per day (95% confidence interval -56.3 to -27.0 minutes/day; p < 0.001) less than participants in the SMART Work & Life-only arm. Sitting time was largely replaced by standing time, and changes in daily behaviour were driven by changes during work hours on workdays. Behaviour changes observed at 12 months were similar to 3 months. At 12 months, small improvements were seen for stress, well-being and vigour in both intervention groups, and for pain in the lower extremity and social norms in the SMART Work & Life plus desk group. Results from the process evaluation supported these findings, with participants reporting feeling more energised, alert, focused and productive. The process evaluation also showed that participants viewed the intervention positively; however, the extent of engagement varied across clusters. The average cost of SMART Work & Life only and SMART Work & Life plus desk was £80.59 and £228.31 per participant, respectively. Within trial, SMART Work & Life only had an incremental cost-effectiveness ratio of £12,091 per quality-adjusted life-year, with SMART Work & Life plus desk being dominated. Over a lifetime, SMART Work & Life only and SMART Work & Life plus desk had incremental cost-effectiveness ratios of £4985 and £13,378 per quality-adjusted life-year, respectively.

Limitations

The study was carried out in one sector, limiting generalisability.

Conclusions

The SMART Work & Life intervention, provided with and without a height-adjustable workstation, was successful in changing sitting time.

Future work

There is a need for longer-term follow-up, as well as follow-up within different organisations.

Trial registration

Current Controlled Trials ISRCTN11618007.

Attitudes towards Exercise, Leisure Activities, and Sedentary Behavior among Adults: A Cross-Sectional, Community-Based Study in Saudi Arabia

Background: Sedentary behavior has received increased attention as a threat to public health all around the world. A global effort has been made to avoid the spread of noncommunicable diseases (NCDs) that are associated with poor lifestyle practices, which rely on public awareness. As a result, the purpose of this study was to analyze the attitudes toward exercise, leisure activities, and sedentary behaviour among adults in Saudi Arabia. Methods: A cross-sectional study was conducted among individuals living in the Riyadh Region in Saudi Arabia. The questionnaire (26 items) used in this study was divided into four sections, and the first section comprised demographic and basic information of the respondents (6 items). The second section asked the respondents about the time spent exercising and sedentary time spent (6 items), the third section of the study comprised eight questionnaires about the frequency of sedentary activity performed during their leisure time, and the last section was about the attitude towards sedentary behavior (6 items). Descriptive and analytical statistics were done to describe the study findings. Data were analyzed using SPSS version 27. Results: The current findings revealed that 44% (n = 305) of the respondents performed exercise 1-2 days a week, and 16.7% (n = 116) never performed any exercise. Furthermore, a considerable percentage of the respondents spent >4 h in a day as sedentary. Most of the sedentary time was spent on work relating activities 62% (n = 430), followed by time spent on coffee 36.4% (n = 252), business relating activity 22.5% (n = 156), and social media 8.9% (n = 62). In this study, most of the respondents agreed that sitting for a prolonged time might negatively impact their health. Most of the respondents showed positive attitudes towards sedentary behavior. Males were statistically more likely than females to exercise 1-2 days per week (p < 0.001). Being male and being married were both significantly associated with sedentary behavior (p < 0.001). In addition, there was a significant association between participants' sleeping status and physical activity per week, where those who slept 5-6 h often performed physical activity, indicating a significant difference (p < 0.001) than respondents who slept 7-8 or >8 h. The participant's age was also found to have a significant association with engaging in physical exercise (p < 0.001). Conclusions: The results of this study showed that Saudi adults are highly sedentary and inactive, though knowing the harmful consequences of inactivity. Therefore, a national active living policy must be adopted to discourage inactivity and being sedentary and encourage active living in Saudi Arabia.

Stretching and Self-Myofascial Release in Helicopter Aircrew to Reduce Neck and Back Pain (Phase 1)

INTRODUCTION

This prospective intervention study was designed to determine the efficacy of a standardized Preflight/Postflight Stretches (PPS) protocol to reduce subjective neck and back pain scores in helicopter aircrew. Aircrew transient back and neck pain is well documented, and there is currently no standardized preflight and postflight stretching protocol for Naval Aviation.

METHODS

Subjects were recruited from two carrier air wing MH-60R squadrons at Naval Air Station Jacksonville. These carrier air wing squadrons were selected to control for size (number of aircrew), age, and operational tempo (number of flight hours). Subjects consisted of both pilots and enlisted aircrew. One squadron was designated as the control group, although the second squadron served as the intervention group. Subjects from both groups filled out the questionnaire. Only the intervention group completed the PPS protocol immediately after completing the questionnaire and before departing the squadron spaces for the aircraft outside. Upon landing, the aircrew completed a postflight debrief. Only the intervention group completed the PPS protocol after debrief. Both the intervention and control groups once again completed the questionnaire. Questionnaires were matched by using a generated anonymous subject ID. The amounts of change and pain levels were then compared using the Mann-Whitney test and the Fisher's exact test, respectively.

RESULTS

The Kolmogorov-Smirnov test found the data to be nonparametric. The preflight and postflight overall (P ≤ .001), cervical (P ≤ .001), thoracic (P = .006), and lumbar (P = .004) differences between the control and intervention groups were found to be statistically significant when using the Mann-Whitney test. Preflight and postflight pain differences in the sacral region and "other" section were not found to be statistically significant (sacral, P = .618; others, P = .182). When evaluating the worsening of the pain level, 50 (92%) of the control flights in which PPS was not performed reported worse pain, compared to 21 (61.8%) in the intervention group where PPS was performed. The Fisher's exact test found the association between performing PPS and the worsening in pain to be statistically significant (P = .001) in the overall, cervical, thoracic, and lumbar regions. Therefore, the hypothesis was accepted in regard to overall pain, as well as in the cervical, thoracic, and lumbar regions.

CONCLUSION

Aircrew back and neck pain because of flying is well documented. However, there is no standardized stretching protocol for aircrew to perform immediately preflight or postflight in U.S. Naval Aviation. This study demonstrated that PPS, a simple 5- to 7-min stretching routine, gives aircrew structure and can reduce postflight cervical, thoracic, lumbar, and overall pain. This phase proved to be safe as no adverse events were reported. The prehabilitation aspect could reduce conventional medical intervention, costly pharmacological management of neck and back pain, and be applied to other aviation populations in military and civilian communities.

Increasing physical activity in the vehicle with an interactive seating system in a male sample

An interactive seating system (IASS) was compared to a state-of-the-art massage seating system (MS) regarding the potential of reducing health risks from prolonged sitting in the vehicle. The study investigated if the systems (1) increase heart rate, which is associated with reduced metabolic and cardiovascular risks; (2) activate muscles with the potential to reduce musculoskeletal pain; (3) influence seating comfort and discomfort. The systems were compared in a passenger scenario in a laboratory study (30 male subjects). Only the use of the IASS significantly elevated the heart rate. Muscle activity showed tendencies to increase in the lower back only while using the MS. In comparison, the IASS activated all six captured muscles. Significantly less discomfort was found for the IASS compared to the MS. In comparison to the MS, the IASS showed a substantially higher potential for reducing health risks from static sitting in the vehicle.Practitioner summary: This laboratory study compared the effects of a novel automotive interactive seating system with those of a state-of-the-art massage seating system. Muscle activity, heart rate and discomfort indicated that the IASS has a significantly higher potential to reduce health risks associated with static seating in a vehicle.Abbreviations: AB: air bladder; AC: active condition; ADSS: active dynamic seating system; CLBP: chronic lumbar back pain; ECG: electrocardiography; EMG: electromyography; IASS: interactive seating system; MS: massage seating system; PC: passive condition; PDSS: passive dynamic seating system; RMS: rootmean-square; TI: time interval.

Preliminary investigation of the effects of sitting with and without short active breaks on muscle stiffness assessed with shear-wave elastography

Purpose

The purpose of this preliminary study was to compare the effects of 1-h sitting with and without short active breaks on muscle stiffness as measured by shear-wave elastography (SWE).

Methods

The participants (7 females, 3 males; age: 24.9 ± 1.2 years) completed two (with and without active breaks) 1-h sitting exposures on separate days. Active breaks (2–3 min) were performed at 20 min and 40 min time marks and comprised simple stretching and activation exercises. Before, during (30 min) and after (1 h) of sitting, shear modulus of upper trapezius, lumbar region of erector spinae and rectus femoris muscles was measured with SWE.

Results

Statistically significant effects of sitting exposure in erector spinae muscle stiffness were noted (p = 0.041; η2 = 0.38). There were no other statistically significant effects of sitting exposure or condition (with/without breaks).

Conclusions

Although few statistically significant effects were detected, the trends in this preliminary trial suggest that prolonged sitting increases muscle stiffness and warrants further investigation of short active breaks with larger sample sizes.

Innovative seated vertical lumbar traction allows simultaneous computer work while inducing spinal height changes similar to supine lying

BACKGROUND

Lumbar intervertebral disc height loss has been associated with spinal height change (SHC) and low back pain (LBP), including stenosis. Non-invasive methods to improve disc height loss require forms of lying down, which are unconducive to computer work.

OBJECTIVE

Intermittent vertical traction (VT) integrated with seated computer work may provide ergonomic alternatives for increasing SHC to promote LBP relief. The primary aim was to develop and introduce a safe VT prototype and dosage to induce and measure SHC. Prototype comfort and LBP ratings were exploratory secondary aims.

METHODS

Forty-one participants were stadiometry-measured for pre- and post-intervention SHC from seated VT at 35% body weight removed, supine lying (SL), and sitting at a computer (SIT) without VT. Pain ratings were recorded for those self-reporting LBP. VT prototype evaluations were compiled from a 3-question, 7-point Likert-style survey.

RESULTS

SHC increased by 3.9 ± 3.4 mm in VT, 1.7 ± 3.4 mm in SIT, and 4.3 ± 3.1 mm in SL (P< 0.000). Post hoc findings were significant between VT and SIT (P< 0.000), and SL and SIT (P< 0.000). VT and SL LBP ratings both decreased, but not SIT.

CONCLUSION

Intermittent seated VT is a promising alternative for postural relief during seated computer work, producing SHC similar to lying down without compromising workflow.

The Effects of an Acute Maximal Seated Lumbar Spine Flexion Exposure on Low Back Mechanical Pain Sensitivity

Viscoelastic creep generated in the lumbar spine following sustained spine flexion may affect the relationship between tissue damage and perceived pain. Two processes supporting this altered relationship include altered neural feedback and inflammatory processes. Our purpose was to determine how low back mechanical pain sensitivity changes following seated lumbar spine flexion using pressure algometry in a repeated-measures, cross-sectional laboratory design. Thirty-eight participants underwent a 10-minute sustained seated maximal flexion exposure with a 40-minute standing recovery period. Pressure algometry assessed pressure pain thresholds and the perceived intensity and unpleasantness of fixed pressures. Accelerometers measured spine flexion angles, and electromyography measured muscular activity during flexion. The flexion exposure produced 4.4° (2.7°) of creep that persisted throughout the entire recovery period. The perception of low back stimulus unpleasantness was elevated immediately following the exposure, 20 minutes before a delayed increase in lumbar erector spinae muscle activity. Women reported the fixed pressures to be more intense than men. Sustained flexion had immediate consequences to the quality of mechanical stimulus perceived but did not alter pressure pain thresholds. Neural feedback and inflammation seemed unlikely mechanisms for this given the time and direction of pain sensitivity changes, leaving a postulated cortical influence.

The longitudinal association between working from home and musculoskeletal pain during the COVID-19 pandemic

OBJECTIVE

This study investigates the associations between working from home and the presence of MSP during the COVID-19 pandemic. Working from home often involves a lot of sedentary computer screen work and the home working environment might not be optimally equipped, which can lead to health problems, including musculoskeletal pain (MSP).

METHODS

Longitudinal data from 16 questionnaire rounds of the Lifelines COVID-19 cohort during the first year of the COVID-19 pandemic (March 2020-February 2021) were used. In total, 40,702 Dutch workers were included. In every round, participants reported whether they worked on location, from home, or hybrid. Logistic Generalized Estimating Equations were used to study the association of work situation with the presence of MSP and the presence of severe MSP.

RESULTS

Working from home was associated with higher risks of having MSP in the lower back (OR: 1.05, 95% CI 1.02-1.08), in the upper back (OR: 1.24, 95% CI 1.18-1.31), and in the neck, shoulder(s) and/or arm(s) (OR: 1.18, 95% CI 1.13-1.22). Hybrid working was associated with higher risks of having pain in the upper back (OR: 1.09, 95% CI 1.02-1.17) and in the neck, shoulder(s) and/or arm(s) (OR: 1.14, 95% CI 1.09-1.20). Both home and hybrid workers had higher risks of severe MSP in the different body areas.

CONCLUSION

Home workers, and to a smaller extent hybrid workers, had higher risks of having MSP than location workers during the first year of the COVID-19 pandemic. The results indicate the importance of measures to prevent MSP in future policies involving working from home.

Prevalence of musculoskeletal disorders among taxi drivers in Yaoundé, Cameroon: preventive effect of physical activity

Background

Musculoskeletal Disorders (MSDs) are very common conditions in the workplace. Among professional drivers, there would be an increased risk of developing these disorders. Identifying the associated factors would allow us to better devise effective prevention strategies. Our objective was to determine the prevalence of MSDs among taxi drivers in the city of Yaoundé and to search for associated factors, mainly the level of physical activity.

Methods

We conducted an analytical cross-sectional study of 151 adult male professional taxi drivers. We used a non-probabilistic consecutive and non-exhaustive sampling method. Sociodemographic, anthropometric and occupational data were collected. MSDs over the past 12 months were assessed using the Nordic Questionnaire and physical activity level was determined by the World Health Organization (WHO) Global Physical Activity Questionnaire (GPAQ). Univariate logistic regression models, followed by a multivariate logistic regression, were used to determine factors associated with the presence of MSDs.

Results

The overall prevalence of MSDs was 86.8% (95% CI 80.8 – 91.4); the most affected areas were mainly the lower back (72.8%) the neck (42.4%), and the knees (29.1%). Job dissatisfaction was associated with MSDs (OR = 2.1 95%CI = 1.1–3.9). Most taxi drivers (62.9%) had a low physical activity level and no association was found between the physical activity level and MSDs.

Conclusions

MSDs are common ailments among taxi drivers in Yaoundé (Cameroon). There is a need to think about how to address job dissatisfaction and better identify other associated factors in order to define good prevention strategies.

Prediction of Work-Related Risk Factors among Bus Drivers Using Machine Learning

A recent development in ergonomics research is using machine learning techniques for risk assessment and injury prevention. Bus drivers are more likely than other workers to suffer musculoskeletal diseases because of the nature of their jobs and their working conditions (WMSDs). The basic idea of this study is to forecast important work-related risk variables linked to WMSDs in bus drivers using machine learning approaches. A total of 400 full-time male bus drivers from the east and west zone depots of Bengaluru Metropolitan Transport Corporation (BMTC), which is based in Bengaluru, south India, took part in this study. In total, 92.5% of participants responded to the questionnaire. The Modified Nordic Musculoskeletal Questionnaire was used to gather data on symptoms of WMSD during the past 12 months (MNMQ). Machine learning techniques including decision tree, random forest, and naïve Bayes were used to forecast the important risk factors related to WMSDs. It was discovered that WMSDs and work-related characteristics were statistically significant. In total, 66.75% of subjects reported having WMSDs. Various classifiers were used to derive the simulation results for the frequency of pain in the musculoskeletal systems throughout the last 12 months with the important risk variables. With 100% accuracy, decision tree and random forest algorithms produce the same results. Naïve Bayes yields 93.28% accuracy. In this study, through a questionnaire survey and data analysis, several health and work-related risk factors were identified among the bus drivers. Risk factors such as involvement in physical activities, frequent posture change, exposure to vibration, egress ingress, on-duty breaks, and seat adaptability issues have the highest influence on the frequency of pain due to WMSDs among bus drivers. From this study, it is recommended that drivers get involved in physical activities, adopt a healthy lifestyle, and maintain proper posture while driving. For any transport organization/company, it is recommended to design driver cabins ergonomically to mitigate the WMSDs among bus drivers.

Exploring the relationships between computer task characteristics, mental workload, and computer users' biomechanical responses

Previous biomechanics studies suggest that higher cognitive mental workload when performing office computer tasks may increase the risk of MSDs among office workers. Cognitive workload can be interpreted in terms of task factors (e.g. task complexity and time pressure) and mental workload factors which include mental demand and mental effort. A laboratory study was conducted to further explore how the task and mental workload factors affected computer users' biomechanical responses, specifically the muscle activation levels and sitting postures. Data were collected as 20 participants worked on computer tasks which varied in their levels of task complexity and time pressure. Visual analog scales were used for assessing mental workload factors. Results indicated that the level of mental effort reported, as opposed to the level of task complexity, was associated with changes in participants' biomechanical responses, but primarily occurred when the chair's backrest was not used. Practitioner summary: A study was conducted to investigate the association between computer users' cognitive workload and biomechanical responses when performing computer task. While task complexity was not directly associated with the changes in participants' biomechanical responses, higher reported mental effort was associated with increased biomechanical responses, but only when the participants did not use the backrest on the chair.

The Effect of a Pelvic Support Chair on Sagittal Lumbosacral Alignment in Sitting Position in Patients with Lower Back Pain

Background

A slouched lumbar posture during sitting is risk factor for the low back pain (LBP). Various chairs have been used to maintain sagittal lumbar lordosis and sacral alignment during sitting. We aimed to demonstrate the effect of a pelvic-support chair on the lumbar lordosis and sacral tilt in patients with LBP.

Methods

We recruited 29 patients with non-specific LBP and 11 healthy subjects in South Korea from Apr 2017 to Mar 2018. The sagittal lumbosacral alignment was examined radiographically in three sitting postures: usual, erect, and sitting in a pelvic-support chair. Five angles [the lumbar lordosis, upper lumbar (ULA), lower lumbar (LLA), lumbosacral (LSA), and sacral slope (SS) angles] were compared between the subjects with LBP and healthy subjects in the three sitting conditions.

Results

There were significant differences in the lumbar lordosis, ULA, LLA, LSA, and SS according to sitting condition (P<.05). All five angles were significantly greater when participants sat erect or in a pelvic-support chair than in their usual sitting position (P<.05). ULA and SS were significantly greater when sitting erect than in a pelvic-support chair (P<.05). LLA was significantly greater in controls than in patients with LBP (P=.042).

Conclusion

The sagittal alignment of the lumbosacral region differed significantly among usual, erect, and pelvic-support chair sitting in patients with LBP and controls. Decreased lordotic curve of the lumbar spine in the usual sitting position can be changed in both patients with LBP and healthy subjects by sitting with pelvic support chair.

Local dynamic stability of the trunk after prolonged seating with axial load

Fatigue from prolonged seating with an axial load on the trunk may impair neuromuscular control and spine stability which may elevate risk of low back pain (LBP) for dynamic tasks following seating. The objective of this study was to assess local dynamic trunk stability using the maximum Lyapunov exponent (λ_MAX) with corresponding coactivation patterns to understand possible effects from prolonged seating. An increase in λ_MAX would indicate decreased stability. Twenty participants (10 male, 10 female) performed a controlled, cyclic sagittal flexion task at 40 cycles per minute before and after three hours of seating in a simulated helicopter-seating environment with a weighted vest. A statistically significant decrease was seen in λ_MAX (bits/s) (Pre-Test = 0.654 ± 0.172; Post-Test = 0.829 ± 0.268, p = 0.002), trunk cumulative coactivation index (unitless/s) (Pre-Test = 1.71 ± 0.97; Post-Test = 1.59 ± 0.96, p = 0.0095), and abdominal activation (normalized) (Pre-Test = 0.46 ± 0.17, Post-Test = 0.41 ± 0.18, p = 0.0146) post-seating exposure. Trunk extension was reduced (∼4°, p = 0.0004) during the post-seating cyclic test with slight corresponding increases in flexion. This study provides evidence of potential effects of fatigue from prolonged seating to neuromuscular control, which may have implications for occupations requiring highly dynamic tasks after prolonged seated postures. Future studies would repeat the tests with dynamic environments (i.e., vibration), test the cyclic flexion protocols with different seating interventions, and continue to test the approach to develop a tool to assess back impairment or intervention effectiveness.

Intelligent Posture Training: Machine-Learning-Powered Human Sitting Posture Recognition Based on a Pressure-Sensing IoT Cushion

We present a solution for intelligent posture training based on accurate, real-time sitting posture monitoring using the LifeChair IoT cushion and supervised machine learning from pressure sensing and user body data. We demonstrate our system's performance in sitting posture and seated stretch recognition tasks with over 98.82% accuracy in recognizing 15 different sitting postures and 97.94% in recognizing six seated stretches. We also show that user BMI divergence significantly affects posture recognition accuracy using machine learning. We validate our method's performance in five different real-world workplace environments and discuss training strategies for the machine learning models. Finally, we propose the first smart posture data-driven stretch recommendation system in alignment with physiotherapy standards.

Postural strategies among office workers during a prolonged sitting bout

Sedentary behavior has increased steadily over prior decades, primarily due to increased computer use at work and at home. The total sedentary time per day has been associated with increased risk of cardiometabolic diseases; increased sitting time at work has been associated with musculoskeletal discomfort particularly in the low back. Office workers spend many hours sitting, thus efforts to increase movement through changes of posture (sit to stand) or moving while sitting have been proposed as ways to mitigate the negative effects of prolonged sitting. Yet, few studies have investigated differences in the movement patterns of office workers while sitting performing their actual work. Therefore, the aim of this study was to characterize movement patterns during a prolonged sitting bout and to determine their association with musculoskeletal pain. Twenty-eight office workers participated in this field study that used a pressure sensitive mat to quantify seat pan pressure (4 regions) and trunk sway parameters over a 2-hour bout of computer work. Data were stratified by breakers who stood up at least once within the 2-hour test and prolongers who remained sitting throughout the test. Overall, there was a decreasing trend in trunk sway parameters (mean COP position, sway path, sway area, sway velocity, maximum displacement, and in-chair movements) over time (p < 0.05), with significant changes in sitting strategies. There were significant differences in trunk sway parameters and perceived musculoskeletal discomfort between breakers and prolongers with breakers having more consistent movement while sitting over the prolonged sitting bout (p < 0.05) and lower discomfort ratings. This may indicate that interrupting prolonged bouts of sitting with short periods of standing can maintain sitting movement patterns and reduce the development of musculoskeletal discomfort. Trunk sway monitoring and promoting periodic standing may be useful tools for maintaining in chair movements that may reduce or prevent the onset of musculoskeletal discomfort during prolonged sitting.

Low back pain and risk factors among Taxi drivers in Turkey: a cross-sectional study

BACKGROUND

Taxi drivers have an increased risk of low back pain due to both physical and occupational conditions. This study aims to determine the prevalence of low back pain and occupational risk factors among taxi drivers working in İzmir, Turkey.

METHODS

This study was conducted with 447 taxi drivers at randomly selected taxi stands between April and September 2021. The questionnaire included demographic, individual, and work-related questions; the Nordic Musculoskeletal Questionnaire; and the Back Pain Functional Scale (BPFS).

RESULTS

The prevalence of low back pain in the last year was 49.7%. In multivariate logistic regression analyses, the risk factors for low back pain included having a body mass index of 25-29.9 kg/m2 (OR= 1.67, 95% CI 1.01-2.76) or ≥30 kg/m2 (OR= 2.15, %95 CI 1.19-3.87), no physical activity (OR= 1.66, 95% CI 1.06-2.62), years of work >10 (OR= 3.23, 95% CI 1.89-5.53), no weekly rest period (OR= 3.11, 95% CI 1.42-6.81), having no lumbar support on the driver's seat (OR:1.67, 95% CI:1.05-2.66), or undecisive job satisfaction (OR= 2.07, 95% CI 1.17-3.66). Being undecided about job satisfaction (OR= 2.34, 95% CI 1.15-4.92) and not having physical activity (OR= 2.10 CI 1.08-4.08) were found to be risk factors for reduced BPFS scores.

CONCLUSION

A strong correlation was found between the frequency of low back pain and the BPFS score and occupational factors. Early detection and management of low back pain are critical to avoid increased low back pain and related injuries among taxi drivers.

The Analyses of the Relationship between Physical Activity, Musculoskeletal System Problems, Sleep, and Screen Exposure Time in University students during the Distance Learning Process

Purpose: To investigate the relationship between physical activity, musculoskeletal system problems, sleep, and screen exposure time in university students during the distance learning process. Methods: Three hundred and one students (183 female, 118 male) participated in the study via online survey. The screen exposure time was recorded. The physical activity using Short Form International Physical Activity Questionnaire and pain using Visual Analog Scale were evaluated. Nordic Musculoskeletal System Questionnaire was used to evaluate musculoskeletal symptoms. The Pittsburg Sleep Quality Index was applied for the details of sleep quality. Results: The students had a low level of physical activity (58.8%) and poor sleep quality (70.8%). Musculoskeletal pain was reported in upper back (85%), lower back (85%), neck (79.4%), shoulder (71.4%). The pain was correlated with total sleep quality (r=0.320, p

Can the Borg CR-10 scale for neck and low back discomfort predict future neck and low back pain among high-risk office workers?

Purpose

Perceived discomfort could indicate an early sign of pain, for example, as a result of a biomechanical load on the musculoskeletal system. Assessing discomfort can, therefore, help to identify workers at increased risk of musculoskeletal disorders for targeted intervention development. We aimed: (1) to identify the optimal cut-off value of neck and low back discomfort among office workers and (2) to evaluate its predictive validity with future neck and low back pain, respectively.

Methods

At baseline healthy participants (n = 100) completed questionnaires, including the Borg CR-10 discomfort scale (on a 0–10 scale), and were followed for six months, during which musculoskeletal pain was assessed monthly. Logistic regression analyses were performed to assess the associations of baseline discomfort with the onset of future neck or low back pain. Sensitivity, specificity, and the area under the receiver operating characteristics curve were estimated to identify the optimal discomfort cut-off value predicting future pain.

Results

Borg CR-10 scores ≥ 3.5 for perceived neck and low back discomfort had acceptable sensitivity and specificity to predict future neck and low back pain, respectively. Perceived discomfort at baseline as a dichotomous measure (using the ≥ 3.5 cut-off) was a statistically significant predictor of future neck pain (OR = 10.33) and low back pain (OR = 11.81).

Conclusion

We identified the optimal cut-off value of the Borg CR-10 discomfort scale to identify office workers at increased risk of developing neck and low back pain. These findings might benefit ergonomists, primary health care providers, and occupational health researchers in developing targeted interventions.

Risk factors and prevalence of work-related musculoskeletal disorders in metropolitan bus drivers: An assessment of whole body and hand-arm transmitted vibration

BACKGROUND

Metropolitan bus drivers have higher prevalence of work-related musculoskeletal disorders (WMSDs) due to their nature of work and working environment.

OBJECTIVE

To identify the prevalence of WMSDs and associated risk factors and to conduct real-time testing to evaluate Whole Body Vibration (WBV) and Hand-Arm Vibration (HAV) in buses based on the ISO standards to assess the vibrations levels at different speeds.

METHODS

Participants in this study were 370 full-time male bus drivers from the north and south zones of 13 depots of Bengaluru Metropolitan Transport Corporation (BMTC), Bengaluru, south India. Information regarding WMSDs symptoms during the previous 7 days and 12 months were collected by Modified Nordic Musculoskeletal Questionnaire (MNMQ). WBV and HAV testing was performed and vibration levels were compared with ISO-2631-1 (1997) and ISO-5349-1-2001 standards. It was found that 68.7% of participants reported WMSDs.

RESULTS

Several individuals and work-related factors were found to be statistically significant with WMSDs. From the Gini impurity measure, vibration and road types (Asphalt pavement and Rough road) were considered as vital risk factors associated with WMSDs.

CONCLUSION

From the WBV and HAV evaluations, it was found that for buses on asphalt pavement at > 60 km/h, the vibration level was higher compared to a lower speed. The vibration level exceeded the Exposure Action Value (EAV) on rough roads at all speeds (20km/h, 40km/h and 60km/h) and in several situations considered based on assumptions the vibration level exceeded the Exposure Limiting Value (ELV).

Whole Body Vibrations during Fully Mechanised Logging

This paper seeks to answer the question of whether the magnitude of vibrations affecting the whole body of the harvester operator (WBV) that are generated by the harvester boom is affected by the size of the processed trunk volume, to specify closer, the magnitude of WBVs generated during forest logging, and to localise these WBVs in individual partial operations. For these purposes, the production process, i.e., forest logging, was divided into six partial operations (Searching; Felling; Processing; Unproductive time; Machine movement; Stationary position). WBVs were scanned in the respective partial operations according to standard ISO 2631-1:1997 and the European Directive 2002/44/EC, and then the values were mutually compared. Volumes of processed trunks were recorded, which were then assigned to the given WBV during the respective operations. Research results did not demonstrate a correlation between the size of the transmitted vibrations and the volumes of cut trunks in the partial work operations of Felling and Processing. Neither a difference was found between the individual partial operations with two exceptions: Searching and Felling/Processing and Unproductive time. The research further showed that the average WBV of three partial operations did not meet the daily limit of 0.50 m/s2 permitted by European Directive 2002/44/EC, within a range from 12.20% to 27.02%.

Prevalence and Potential Risk Factors for Occupational Low Back Pain Among Male Military Pilots: A Study Based on Questionnaire and Physical Function Assessment

Objectives: Low back pain (LBP) has negative implications for the military's combat effectiveness. This study was conducted to determine the prevalence and risk factors of LBP among pilots through a questionnaire and physical function assessments.

Methods: Data on the demographic and occupational characteristics, health habits, physical activity, and musculoskeletal injuries of 217 male pilots (114 fighter, 48 helicopter, and 55 transport pilots) were collected using a self-reported questionnaire and physical function assessments.

Results: LBP prevalence was 37.8% in the total cohort and 36.0, 45.8, and 34.5% among fighter, helicopter, and transport pilots, respectively. Multivariate regression analysis revealed that the risk factors significantly associated with LBP were neck pain [odds ratio (OR): 3.559, 95% confidence interval (CI): 1.827–6.934], transversus abdominis activation (OR: 0.346, 95% CI: 0.172–0.698), and hip external rotator strength (OR: 0.001, 95% CI: 0.000–0.563) in the total cohort; neck pain (OR: 3.586, 95% CI: 1.365–9.418), transversus abdominis activation (OR: 0.268, 95% CI: 0.094–0.765), hip external rotator strength (OR: 0.000, 95% CI: 0.000–0.949), and weekly flying hours (OR: 3.889, 95% CI: 1.490–10.149) in fighter pilots; irregular strength training (OR: 0.036, 95% CI: 0.003–0.507) and hip external rotator strength (OR: 0.000, 95% CI: 0.000–0.042) in helicopter pilots; and neck pain (OR: 6.417, 95% CI: 1.424–28.909) in transport pilots.

Conclusions: High volume flight schedules and weak core muscle functions have significant negative effects on pilots' back health. LBP is commonly associated with high weekly flying hours, worsening neck pain, transversus abdominis insufficient activation, and reduced hip extensor/rotator strength. Risk factors vary among pilots of different aircraft. Thus, specific core muscle training would be especially important for military pilots.

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).

Long-Term Prevalence and Risk Factors of Musculoskeletal Disorders among the Schoolteachers in Hail, Saudi Arabia: A Cross-Sectional Study

Background

Musculoskeletal disorders (MSDs) are affecting up to 95% of teachers and are considered a primary occupational health hazard leading to absenteeism, early retirement, and lower quality of life and teaching quality.

Aim

The current study is aimed at exploring the prevalence and risk factors of MSDs among the schoolteachers in Hail, Saudi Arabia.

Methods

A cross-sectional study was conducted online among the teachers in Hail City using the Nordic Musculoskeletal Questionnaire. Teachers were randomly selected from randomly selected high schools. Teachers with at least 1 year experience were recruited for the study. Descriptive statistics, Cochran's Q test, and binominal regression were used to investigate the prevalence of MSDs among such teachers and to determine if the percentage of MSDs differed by anatomical region and risk factor (one hundred forty-five males and 106 females filled out the questionnaires).

Results

The prevalence of MSDs in the last 12 months was 93.63% (235 of 251 teachers). Interestingly, 91% of the affected participants (214 of 235 teachers) complained of MSDs in more than one anatomical region. The most affected site was the lower back (183 of 251 teachers, 72.91%), followed by the shoulders (168 of 251 teachers, 66.93%), and the least affected sites were the elbows (45 of 251 teachers, 17.93%). The females showed a higher prevalence of MSDs than the males. Only gender was a significant risk factor for shoulder and neck MSDs (p < 0.02).

Conclusion

Overall, the findings of the current study suggest a high prevalence of MSDs among teachers, especially in the lower back and shoulders. The affected teachers should learn more about biomechanics and ergonomics and should engage in exercise to improve their health. Future studies should focus on identifying the biomechanical and ergonomic risk factors of MSDs and on designing MSD prevention programmes to reduce the burden of MSDs.

Associated Risk Factors with Low Back Pain in White-Collar Workers-A Cross-Sectional Study

Objective: The purpose of the study was to compare the pressure pain threshold (PPT) of soft tissue and the curvatures of the spine in a sitting position and to estimate associated physical risk factors with low back pain (LBP) in young adults. Subjects: White-collar workers (n= 139), both women (n = 51) and men (n = 88) were separated into a control group (n = 82) and a low-intensity LBP (NRS < 3) (n = 57). Methods: The PPTs were tested utilizing the Wagner algometer. The curvatures of the spine were measured employing the photogrammetric method. In the logistic regression model, the odds ratio (OR) was estimated with ±95% confidence interval (CI) indicating the probability of the reported LBP. Results: The PPTs of soft tissue (OR = 1.1; CI = 1.02−1.19; p < 0.05) and the angle of the thoracolumbar spine in the everyday, habitual sitting position (OR = 1.19; CI = 1.05−1.34; p < 0.05) were associated with low-intensity LBP in female subjects. Additionally, the low intensity LBP were associated with the angles of the torso (OR = 1.14; CI = 1.01−1.29; p < 0.05) and the lumbosacral spine in the corrected sitting position (OR = 1.06; CI = 0.98−1.15; p > 0.05) and BMI (OR = 1.56; CI = 0.84−2.90; p > 0.05) in male subjects. Conclusion: Individual risk factors were associated with the low-intensity LBP only in females utilizing the PPT and the thoracolumbar angle in the habitual sitting position study factors. Men from the LBP group did not effectively correct the lumbosacral angle. Therefore, re-educated, self-corrected posture with specific postural training would be expected to improve proprioception in postural control capacity and result in decreasing pain.

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.

Multisite musculoskeletal pain in the general population: a cross-sectional survey

BACKGROUND

Epidemiological studies focusing on multisite musculoskeletal pain have revealed that the prevalence of multisite pain is high in general populations.

OBJECTIVE

To ascertain the prevalence of multisite musculoskeletal pain in the last 12 months and in the last seven days, in a population-based sample and investigate its association with demographic, socioeconomic, behavioral, reported morbidity and ergonomic variables.

DESIGN AND SETTING

Cross-sectional population-based survey in Bauru, São Paulo (Brazil).

METHODS

600 individuals were interviewed. The following data were collected: participants' characteristics, through a precoded questionnaire; physical activity level, through the International Physical Activity Questionnaire; and musculoskeletal symptoms, through the Nordic questionnaire. Descriptive, bivariate and Poisson regression analyses were performed.

RESULTS

The prevalence of multisite musculoskeletal pain was 46.5% (confidence interval, CI 42.5 to 50.5) in the last 12 months and 26.1% (CI 22.8 to 29.8) in the last seven days. The variables associated with multisite pain in the last 12 months were female sex, presence of hypertension, diabetes mellitus or depression, watching TV more than three times a week and working in a seated position. Formerly smoking was a protection factor. The variables associated with multisite pain in the last seven days were female sex, age group 60 years and over, low income, presence of comorbidities of hypertension, diabetes mellitus or depression and working in a seated position.

CONCLUSION

There was high prevalence of multisite musculoskeletal pain, which was associated with demographic, socioeconomic, work-related, electronic device-related and reported morbidity variables.

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.

Long working hours and risk of 50 health conditions and mortality outcomes: a multicohort study in four European countries

BACKGROUND

Studies on the association between long working hours and health have captured only a narrow range of outcomes (mainly cardiometabolic diseases and depression) and no outcome-wide studies on this topic are available. To achieve wider scope of potential harm, we examined long working hours as a risk factor for a wide range of disease and mortality endpoints.

METHODS

The data of this multicohort study were from two population cohorts from Finland (primary analysis, n=59 599) and nine cohorts (replication analysis, n=44 262) from Sweden, Denmark, and the UK, all part of the Individual-participant Meta-analysis in Working Populations (IPD-Work) consortium. Baseline-assessed long working hours (≥55 hours per week) were compared to standard working hours (35-40 h). Outcome measures with follow-up until age 65 years were 46 diseases that required hospital treatment or continuous pharmacotherapy, all-cause, and three cause-specific mortality endpoints, ascertained via linkage to national health and mortality registers.

FINDINGS

2747 (4·6%) participants in the primary cohorts and 3027 (6·8%) in the replication cohorts worked long hours. After adjustment for age, sex, and socioeconomic status, working long hours was associated with increased risk of cardiovascular death (hazard ratio 1·68; 95% confidence interval 1·08-2·61 in primary analysis and 1·52; 0·90-2·58 in replication analysis), infections (1·37; 1·13-1·67 and 1·45; 1·13-1·87), diabetes (1·18; 1·01-1·38 and 1·41; 0·98-2·02), injuries (1·22; 1·00-1·50 and 1·18; 0·98-1·18) and musculoskeletal disorders (1·15; 1·06-1·26 and 1·13; 1·00-1·27). Working long hours was not associated with all-cause mortality.

INTERPRETATION

Follow-up of 50 health outcomes in four European countries suggests that working long hours is associated with an elevated risk of early cardiovascular death and hospital-treated infections before age 65. Associations, albeit weak, were also observed with diabetes, musculoskeletal disorders and injuries. In these data working long hours was not related to elevated overall mortality.

FUNDING

NordForsk, the Medical Research Council, the National Institute on Aging, the Wellcome Trust, Academy of Finland, and Finnish Work Environment Fund.