Low back pain and other work-related musculoskeletal problems among physiotherapists

This technical note reports the findings of a self-administered questionnaire regarding low back pain (LBP) and other musculoskeletal problems completed by 113 physiotherapists (15% of the active physiotherapists in the Republic of Slovenia). The study revealed that the overall incidence among the sample population of physiotherapists is 73.7% and the most prominent factor appears to be the age of the respondents. The only triggering factor for LBP within the physiotherapy profession appears to be handling of dependent patients.     

The impact of a sloped surface on low back pain during prolonged standing work: A biomechanical analysis

Background

Occupations that require prolonged periods of standing have been associated with increased reports of musculoskeletal disorders including low back pain. Previous work has utilized a prospective design of functionally inducing low back pain in previously asymptomatic individuals during a prolonged standing task. Increased trunk and gluteus medius muscle co-activation has been found in previously asymptomatic individuals who developed pain during standing compared with individuals who did not develop pain.

Purpose

The purpose of this study was to investigate the subjective and biomechanical responses of known pain developers and non-pain developers (previously determined during level standing) when exposed to the same prolonged standing task protocol completed while standing on a ±16° sloped surface.

Results

Overall low back pain scores were reduced by 59.4% for the pain development group, identified in level standing, when using the sloped surface. There was a marked decrease in the co-activation of the bilateral gluteus medius muscles in the known pain developers when standing on the sloped surface compared with level standing. However the non-pain developer group responded in the opposite direction by having an increase in the co-activation of these muscles, although they did not have a commensurate increase in low back pain. There were changes in both the postural and joint-loading variables examined. These changes were minimal and in most cases the sloped surface produced responses that bracketed the postures and loading magnitudes found in level standing depending on whether the participant was standing on the +16° or −16° surface.

Conclusions

The sloped surface resulted in decreased subjective low back pain during prolonged standing. There were also associated biomechanical changes resulting from using a sloped surface during prolonged standing. These positive findings were supported in an exit survey satisfaction rating with 87.5% indicating that they would use the sloped surface if they were in an occupational setting that required prolonged standing work.     

Preparation of dynamic posture and occurrence of low back pain

Abstract

Improper posture is considered as one of the causes for low back pain. This study focused attention on low back pain that occurs when people adopt a dynamic posture. Low back pain in attendants was investigated as a typical example of low back pain in a dynamic posture. When multi-dimensional quantification III was applied to the results of the investigation, low back pain was found to occur in six postural patterns: bending knee posture, the posture of lifting and holding a light object, the posture of tilting the trunk, working posture to push a cart, the posture of turning or lifting a cart, and the posture of stretching. This survey found that low back pain frequently occurred when an unexpected load was imposed on the lumbar region and experiments were conducted to simulate the unexpected loading of this region. The experimental results showed that lumbar muscular activity was not fast enough to cope with the load and resulted in an increased swaying of the trunk. This swaying was considered to induce a load on the lumbar region. It is concluded that low back pain can be prevented if an appropriate preparatory set is taken.     

Effects of personal,psychosocial and occupational factors on low back pain severity in workers

Low back pain (LBP) remains the most common work-related musculoskeletal disorder (WMSD). While most of the LBP research has focused on occupational risk factors, other underlying causal mechanisms may exist since not all workers performing the same task develop an injury. Previous research has identified three primary risk factor categories for LBP (occupational, personal and psychosocial factors); however, few studies have investigated the impact of cross categorical risk factor interactions on LBP. The objective of this study was to investigate the effects of occupational, personal and psychosocial factors, and their interactions, on LBP severity in a population of workers currently suffering from LBP. Sixty LBP patients recruited for the study through local physicians and local announcements, completed questionnaires relating to identified occupational, personal and psychosocial risk factors, and completed an Oswestry Disability Index (ODI). Multiple regression models for predicting LBP severity were developed for each risk factor category and for a combined risk factor model (which included factors from all three risk factor categories) that included two-way interactions. Results showed that the final model consisted of both main effects and interaction terms between risk factor categories and had an adjusted R² value of 0.85, a significant improvement over models developed for the individual categories. These findings illustrate the need to consider all three broad categories of risk factors simultaneously in predicting injury status and in developing effective potential intervention efforts.     

ERRORS IN THE PERCEPTION OP RAILWAY SIGNALS

This paper is based upon observations of train drivers at work, and defines certain kinds of errors which may be made by drivers in perceiving railway signals. It discusses hypotheses relating incidence of error to various factors. It is suggested that the investigation of hypotheses of this kind, derived from the observation of the normal performance of the operative, is a valid method of accident study.     

Static and dynamic characteristics of the trunk and history of low back pain

A pilot research was undertaken to study the relationship between static and dynamic characteristics of the trunk and the existence of low back pain. Isoinertial dynamic tests were performed using an ISOSTATION B200 dynamometer on 33 non LBP workers and 11 LBP workers. Ranges of motion and isometric strengths were not systematically different between LBP and non LBP, while these differences were significant for the average absolute velocities during dynamics tests against 25 or 50% of the isometric torques. For the mean quadratic velocity during tests against 50% of the isometric torques, a value of 75 degrees per second can be proposed as a threshold for discriminating between LBP and non LBP. The sensitivity and specificity of this test increased to 92 and 88% respectively when the past LBP history was also taken into account. This confirms that trunk velocity during isoinertial movements is very sensitive to low back condition and research should be pursued to identify the biomechanical reasons for this and possibly differentiate between the different symptoms of LBP.     

The interaction between skill, postures, forces and back pain in wool handling

Wool handling is an important rural occupation where workers process 200 or more fleeces daily, separating them into various quality components. Loads and postures they experience carry substantial risk of low back pain (LBP). Although a formal skill training structure exists, interaction with loads and LBP is unknown. We examined whether skill and LBP influenced trunk postures and loads of 60 wool handlers representing 3 skill levels. LBP prevalence ranged from 20% for junior (lowest skill) to 45% for open class (highest skill) wool handlers. Open class wool handlers demonstrated increased lateral bend and more axially twisted postures, generating greater medio-lateral shear forces and lateral bend and axial twist moments. LBP was associated with open class wool handlers spending more time in severe axially twisted postures. These findings suggest that skill-based training needs to be reviewed to reduce the quantity of axially twisted posture which may help reduce the prevalence of LBP in this workforce.     

Effectiveness of an ergonomic intervention on work-related posture and low back pain in video display terminal operators: A 3 year cross-over trial

This study investigated the effectiveness of a workstation ergonomic intervention for work-related posture and low back pain (LBP) in Video Display Terminal (VDT) workers. 100 VDT workers were selected to receive the ergonomic intervention, whereas 100 were assigned to a control group. The two groups were then crossed-over after 30 months from baseline. Follow-ups were repeated at 5, 12, and 30 months from baseline and then at 6 months following crossover. Outcomes: Work-related posture and LBP point-prevalence using the Rapid Entire Body Assessment method and a Pain Drawing, respectively. The ergonomic intervention at the workstation improved work-related posture and was effective in reducing LBP point-prevalence both in the first study period and after crossover, and these effects persisted for at least 30 months. In conclusion, our findings contribute to the evidence that individualized ergonomic interventions may be able to improve work-related posture and reduce LBP for VDT workers.     

Ergonomie guidelines for the prevention of low back pain at the workplace

The aim of this paper is to discuss the usefulness of common ergonomie guidelines for preventing low back pain at the workplace. Sixteen recent ergonomie, biomechanical and epidemiological books were reviewed to obtain common ergonomie guidelines for both static and dynamic work (e.g., sitting, lifting), and to obtain an overview of commonly-observed individual and work-related risk factors of low back pain. The results show that the aspects of work for which ergonomie guidelines are presented generally correspond to work-related risk factors as shown by epidemiological studies. However, in quantitative terms the guidelines show a great variety, possibly due to differences in criteria. In certain cases, it is not clear whether or not the guidelines are based on back load or back pain data, due to lack of references. It appears that many guidelines are based upon a combination of back load criteria and other criteria, although it is unknown how these criteria are combined. Hence, many guidelines do not apply specifically to low back pain.

With certain exceptions, most guidelines do not take into account individual factors, although epidemiological studies indicate that several factors such as age, strength, fitness, psychosocial factors, and history of back pain should be considered. However, because of the qualitative character of most current epidemiological studies, results cannot be readily implemented into quantitative ergonomie guidelines.

The above general results are discussed with examples. It is concluded that there is a great need for ergonomie guidelines that apply specifically to low back pain, and for quantitative epidemiological data on which these guidelines may be based.     

Effects of positioning optimization in an alternative computer workstation for people with and without low back pain

The aim of this study was to measure the impact of positioning optimization on typing performance and user comfort for people with and without low back pain (LBP) in alternative working postures. Participants completed a series of typing tests in each of five randomly ordered alternative working postures ranging from upright to fully supine. Typing accuracy and typing speed were recorded as were subjective measures of overall comfort and body part discomfort. The impact of positioning optimization of the monitor, keyboard, and arm supports was determined by comparing results from an “Optimized” test study protocol (n = 27) with those from a “Non-Optimized” test study protocol (n = 26). The results indicate a significant improvement in user comfort with the optimized positioning, but no significant differences in typing performance between the two test protocols. However, in both tests the slowest typing speeds occurred in the fully reclined and zero gravity working postures. Results of the user comfort scores indicated that for the Non-Optimized test, all alternative working postures were less comfortable than the upright posture. Whereas, in the Optimized test the tilted and reclined postures were comparable to the upright working posture and only the zero gravity posture was viewed as less comfortable.

Relevance to industry

Understanding the importance of position optimization for VDT operators in alternative working postures will provide valuable information toward the development of more comfortable and more accommodating computer workstations.     

Participation in workplace design with reference to low back pain: a case for the improvement of the police patrol car

Thirty Canadian police officers, divided into six groups, participated in the redesign of the interior of the patrol car. Three of the groups consisted of individuals having a history of low back disease. The effect of participating in a design process on the characteristics of the final design and on the perception of the low back pain was studied in a semi-experimental setting. The participants developed a strong commitment to the participatory design process, which was reflected in their productions. The differences between participants with and without a history of a low back disease was not marked. The former tended to stress posture-related elements in their analysis and design.     

Using a deep learning network to recognise low back pain in static standing

Abstract

Low back pain (LBP) remains one of the most prevalent musculoskeletal disorders, while algorithms that able to recognise LBP patients from healthy population using balance performance data are rarely seen. In this study, human balance and body sway performance during standing trials were utilised to recognise chronic LBP populations using deep neural networks. To be specific, 44 chronic LBP and healthy individuals performed static standing tasks, while their spine kinematics and centre of pressure were recorded. A deep learning network with long short-term memory units was used for training, prediction and implementation. The performance of the model was evaluated by: (a) overall accuracy, (b) precision, (c) recall, (d) F1 measure, (e) receiver-operating characteristic and (f) area under the curve. Results indicated that deep neural networks could recognise LBP populations with precision up to 97.2% and recall up to 97.2%. Meanwhile, the results showed that the model with the C7 sensor output performed the best.

Practitioner summary: Low back pain (LBP) remains the most common musculoskeletal disorder. In this study, we investigated the feasibility of applying artificial intelligent deep neural network in detecting LBP population from healthy controls with their kinematics data. Results showed a deep learning network can solve the above classification problem with both promising precision and recall performance.     

Low back pain among mineworkers in relation to driving,cold environment and ergonomics

Objectives: We aimed to study the association between low back pain (LBP) and exposure to low temperature, wet clothes, heavy lifting and jobs that involve whole body vibration (WBV) in a population of miners. Methods: Health and personal data were collected in a population study by a questionnaire. A total of 3530 workers from four mines participated in the study. Results: 51% of the workers reported LBP within the last 12 months. The adjusted odds ratio for LBP was above unity for working with wet clothes (1.82), working in cold conditions (1.52), lifting heavy (1.54), having worked as a driver previously (1.79) and driving Toro400 (2.61) or train (1.69). Conclusion: Wet clothing, cold working conditions, heavy lifting, previous work as a driver and driving certain vehicles were associated with LBP, but vehicles with WBV levels above action value were not. For better prevention of LBP, improved cabin conditions and clothing should be emphasised.     

Implementation of ergonomic programs to reduce sick leave due to low back pain among nickel mining operators

Whole body vibration (WBV) has been recognized as a main risk factor for low back pain (LBP) in coal mining activities. Heavy equipment operators in nickel mining may be exposed to a higher LBP risk due to the land condition of the overburden overlying nickel deposits, which is less stable than that of coal deposits. This report summarizes the efforts of a nickel company in managing LBP complaints among mining operators. The programs included risk assessment and mitigation, musculoskeletal complaint management, LBP training, and macroergonomic intervention. These programs were integrated into the occupational health management system of the company. Within a 3-year period, a decrease in LBP-related sick leave was reported. The present report shows how ergonomic programs may help to manage LBP and could be extended to other musculoskeletal cases.     

Prevalence and associated risk factors of low‐back pain in textile fishing net manufacturing

This study examined the 7‐day prevalence of low‐back pain (LBP; i.e., pain within the preceding week of the survey) and identified associated factors, including working posture, for a population of fishing net assembly workers. LBP is a serious problem in manual work with high prevalence and affects worker absenteeism. A cross‐sectional survey study was conducted among textile fish net industrial workers using a structured questionnaire (hand delivered by researchers and independently completed by workers). The 7‐day prevalence of LBP in this study was 68.6% (95% confidence interval [CI]: 65 to 72%). Work factors significantly related to LBP included prolonged standing and walking. Workers 35 years old or greater were significantly more likely to experience LBP within the past 7 days preceding the survey than were those 34 years old or less (adjusted odds ratio [ORadj] = 4.9; 95% CI: 2.4 to 10.3; p = .0001). Other significant factors associated with LBP included posture position, specifically stooping (ORadj = 1.6; 95% CI: 1.0 to 2.3; p = .033), lifting (ORadj = 1.6; 95% CI: 1.1 to 2.4; p = .025), and high concentration jobs (ORadj = 1.9; 95% CI: 1.3 to 2.7; p = .001), respectively. LBP among textile fish net workers is a serious problem meriting ergonomic evaluation and design of control measures for reducing worker exposure to risk factors. Work characteristics were more significantly associated with LBP than were individual characteristics. Factories need to consider adjusting work conditions to prevent worker low‐back injuries. © 2012 Wiley Periodicals, Inc.     

Trunk posture: reliability, accuracy, and risk estimates for low back pain from a video based assessment method

It has been recently reported that both dynamic movement characteristics, as well as the duration of postures adopted during work, are important in the development of low back pain (LBP). This paper presents a video-based posture assessment method capable of measuring trunk angles and angular velocities in industrial workplaces. The inter-observer reliability, system accuracy, and the relationship of the measured exposures to the reporting of low back pain are reported. The video analysis workstation consisted of a desktop computer equipped with digital video capture and playback technology, a VCR, and a computer game type joystick. The operator could then use a joystick to track trunk flexion and lateral bending during computer-controlled video playback. The joystick buttons were used for binary input of twisting. The inter-observer reliability for peak flexion and percentage of time spent in posture category variables were excellent (ICC>0.8). Lower reliability levels were observed for peak and average velocity and movement related variables. The video analysis system time series data showed very high correlation to the criterion optoelectronic imaging system (r=0.92). Root mean square errors averaged 5.8° for the amplitude probability distribution function data. Trunk flexion variables including peak level, peak velocity, average velocity indicators, and percent time in flexion category indicators all showed significant differences between cases and controls in the epidemiological study. A model consisting of the measures peak trunk flexion, percent time in lateral bend and average lateral bending velocity emerged after multivariable analysis for relationship to low back pain.

Relevance to industry

Risk of injury for the low back is multifactorial. The trunk position and movement velocity are emerging as important parameters. This analysis confirms the importance of these factors and demonstrates the utility of a video-based method to measure them in industrial settings.     

The role of whole-body vibration in back pain: A cross-sectional study with agricultural pilots

ObjectiveA cross-sectional study was conducted to investigate the role of whole-body vibration as a risk factor for spinal musculoskeletal symptoms among agricultural pilots.MethodThe study was conducted in two stages that included measuring the pilots’ exposure to whole-body vibration during the flight procedures and applying a self-administered questionnaire about musculoskeletal symptoms of the spine.ResultsNone of the four aircraft texted exposed the pilot above the Exposure Limit Value (ELV) established by the standards. However, in a few specific situations, two of them exceeded the Exposure Action Value (EAV). About 62% of the pilots who operated these aircraft reported some musculoskeletal symptoms of the spine in the last few 12 months.ConclusionUsing the data from this study, it was possible to calculate the odds ratio of the agricultural pilot suffering low back pain, based on eight personal and work-related factors.Relevance for the industryBased on the results of the present study, it was possible to define strategies to reduce whole-body exposure in agricultural aircraft and, consequently, improve the pilots’ health. Strategies included management of the exposure and aircraft improvement.     

The prevalence and characteristics of back pain among school children in New Zealand

A cross-sectional survey among 245 children was conducted to establish the prevalence and characteristics of back pain in school children aged 11–14 years. A self-complete questionnaire was used to ascertain demographic details, pain prevalence, psychosocial parameters, school and leisure activities and family characteristics. In the last month, 58% of children had experienced spinal pain. In total, 31% of children reported that pain occurred in one part of the back, while 28% stated that pain presented in more than one spinal region. Pain in the last month was found to be equally prevalent in the low back (35%) and neck (36%) regions. Low back pain was associated with the most severe pain and pain lasting for the longest duration when compared with the upper back and neck regions. Further research should be directed towards investigating pain in the neck region and understanding the characteristics of symptom co-occurrence.

Statement of Relevance:A survey was conducted to establish the prevalence and characteristics of back pain in school children. The results provide additional evidence that back pain is a serious problem in children aged 11–14 years, whilst also indicating widespread co-occurrence of pain in the neck, upper back and lower back spinal regions.     

One lumbar extension training session per week is sufficient for strength gains and reductions in pain in patients with chronic low back pain ergonomics

Chronic low back pain (CLBP) is the leading cause of absenteeism from the workplace and research into exercise interventions to address this problem is required. This study investigated training frequency for participants with CLBP. Participants either trained once a week (1 × week, n = 31), or twice a week (2 × week, n = 20) or did not (control group, n = 21). Participants were isometric strength tested in weeks 1 and 12 and trained dynamically either 1×week (80% of maximum) or 2×week (80% and 50%). The results (pre vs. post) showed significant increases in maximal strength, range of motion and reductions in pain for both training groups. Pain scores for the 1 × week and 2 × week both reached minimal clinical improvement change unlike the control group. Thus, one lumbar extension training session per week is sufficient for strength gains and reductions in pain in low back pain in CLBP patients. PRACTITIONER SUMMARY: CLBP is the leading cause of absenteeism from the workplace. The present study using a modified randomised control trial design investigated exercise training frequency for participants with CLBP. One lumbar extension training session per week is sufficient for strength gains and reductions in low back pain in CLBP patients.