|Year : 2022 | Volume
| Issue : 2 | Page : 211-219
Musculoskeletal Disorders: Prevalent predicaments among carpenters of West Bengal, India
Kanu Gopal Biswas, Piya Majumdar, Subhashis Sahu
Department of Physiology, Ergonomics and Occupational Physiology Laboratory, University of Kalyani, Kalyani, West Bengal, India
|Date of Submission||28-Mar-2022|
|Date of Decision||30-Jun-2022|
|Date of Acceptance||04-Jul-2022|
|Date of Web Publication||06-Dec-2022|
Associate Professor, Ergonomics and Occupational Physiology Laboratory, Department of Physiology, University of Kalyani, Kalyani, Nadia-741235, West Bengal
Source of Support: None, Conflict of Interest: None
BACKGROUND: Carpentry and related jobs are the major occupations for a large number of people in the rural and urban areas of India which is mainly unorganized.
AIMS AND OBJECTIVES: Carpentry work is unorganized informal sectors, particularly in developed countries such as India, and there is a lack of data on musculoskeletal disorders and the issues are being undermined nowadays, so we intend to study and evaluate the prevalence of musculoskeletal disorders among carpenters, analyzing major causes behind such predicaments with a special emphasis on working posture.
MATERIALS AND METHODS: For the present study, 148 male carpenters aged between 20-60 years were randomly taken from different wooden furniture manufacturing units in West Bengal, India, and 148 referent subjects from different working sectors with similar socioeconomic status who have been categorized depending upon their experience. Socio-demographic features along with physical measures, physiological status, working posture, and discomfort at different body parts were evaluated following standard protocol.
RESULTS: Based on the observations, it was found that most of the carpenters were suffering from work-related health predicaments, mainly musculoskeletal problems due to awkward working posture. Some of the working postures adopted by carpenters were identified as very strenuous. They complain about pain during working hours and also during the rest period. It was observed that the head, neck, shoulder, arm, elbow, wrist, upper back, lower back, waist, leg, knee, and ankle were majorly affected areas due to their repetitive nature of work with awkward posture. Body part discomfort rating showed that the lower back was mostly stressed and the elbow and leg were least. It was also found that their working place and their working environment and unergonomic tools make work more strenuous.
CONCLUSION: So, some ergonomic interventions are required to improve the quality of life of the carpenter work, and scheduled rest-pause may enable the workers to recover from strain.
Keywords: Body part discomfort, carpenter, musculoskeletal problems, unorganized sector, working posture
|How to cite this article:|
Biswas KG, Majumdar P, Sahu S. Musculoskeletal Disorders: Prevalent predicaments among carpenters of West Bengal, India. BLDE Univ J Health Sci 2022;7:211-9
In West Bengal as well as all over the world, wooden furniture-making industries are abundantly found. A large number of people of West Bengal are also found to be engaged in carpentry work both in the rural and urban areas, but usually, the manufacturing units are small-scale industries that are unorganized. The worker known as carpenters who perform their job in this industry is unorganized laborers. Most of the carpenters are daily wage laborers with lower socioeconomic backgrounds.
Carpenters construct, repair furniture, and install building frameworks and structures made from wood and other materials. Their work is performed both indoors and outdoors depending on the construction project where the work environment is found to be unsuitable for the workers. Their job prospect is physically demanding with higher chances of occurrence of injuries and illness. Unfortunately, they are unaware of related occupational safety and health problems. They are affected by different occupational hazards such as repeated motion; working in an awkward posture; exposure to heat, cold, dust, chemicals, and biological agents; and manual material handling. The reports on occupational health problems are scanty.
Carpenters suffer from various occupational health problems due to different stressors in their work; musculoskeletal disorders (MSDs) are the most common self-reported work-related illness among them that involves impairment in the muscle, tendon, bones, cartilages, and ligaments of the body. It includes all forms of musculoskeletal system ranging from light transitory disorders to irreversible disabling injuries. It is the manifestation of the postural strain and one of the leading causes of disability of people during working life. Occupational factors cause aggravation of MSDs, which ranks first among the health problems in frequency, resulting in loss of time during work.
MSDs are the leading cause of occupational health in developed and industrially developing countries. Risk factors are known to include workplace activities such as heavy lifting and repetitive tasks. MSDs represent a major occupational problem and a significant cause of morbidity. Many studies have shown an association between MSDs and workplace factors.
The hazardous working conditions, old working methods, unorganized work, and primitive working tools are factors that impose stress on the workers and hinder productivity. During the making of wooden furniture, some postures adopted by the carpenters are strenuous, which leads to body pain and ultimately MSDs. According to the National Institute for Occupational Safety and Health 1997, work-related musculoskeletal injuries occurred in the muscles, ligaments, tendons, or nerves due to excessive stress on the musculoskeletal system and the majority of these injuries are due to recurrent movements. A study on more than 10,000 carpenters in the state of Washington reported that back pain accounted for the largest group of the workers' compensation claims filled for MSDs. A study showed that symptom-derived weighted mean difference data are useful in estimating the prevalence of cumulative trauma disorders among carpenters.
Previously, it was also reported that carpenters often work in awkward postures and are affected by musculoskeletal problems like pain in the low back, neck, and wrist. The intensity of pain feeling, age, and year of exposure was significantly associated with the risk level. However, the persistence of musculoskeletal strain for a prolonged period might be a sign of MSDs.,,
Most of the carpenters engaged in unorganized informal sectors, especially in developed countries like India and there is a dearth of data on the MSD and the issues are undermined nowadays, so we aim to study and evaluate the prevalence of MSDs among carpenters analyzing major causes behind such predicaments with special emphasis on working posture.
| Methodology|| |
For the present study, data were randomly collected to avoid biases from one hundred forty-eight adult male carpenters having a minimum of 1 year of working experience. The subjects with chronic illnesses were excluded from the study. One hundred forty-eight personnel were taken as referent subjects from different working sectors of West Bengal with similar economic backgrounds residing at the same or the nearest localities (not too far away) and were not exposed to any kind of respiratory dust (specifically wood dust). Most of the participants were from local shops (furniture, groceries, garments, and stationery) having ownership, deals with customers, involved in sales, deal paperwork, etc. The exposed subjects were divided into two groups subsequently based on their working experience. Group A had more than 10 years of experience and Group B had <10 years of experience.
Participants with any sort of genetic, congenital, or pathological condition were exempted from the study.
All the experiments were performed upon prior permission and ethically approved by the Departmental Research Committee, University of Kalyani, following the Helsinki Declaration.
All the recruited participants were enquired regarding age, marital status, presence or absence of children, years of experience, as well as health behaviors such as alcohol intake, smoking habits, disease diagnosis, and use of medicine. The socioeconomic status of the workers and the referent subjects were determined using Modified Kuppuswami Socioeconomic Status questionnaire.
Assessment of body part discomfort and pain prevalence
Modified Nordic questionnaire and Oswestry Low Back Pain Disability Questionnaire were administered for finding any MSDs of the workers., 12-Item General Health Questionnaire 12 (GHQ12) was administered for finding physiological stress due to their carpentry work. By the questionnaire method, pain in different body parts was randomly asked to the workers, and according to their answer, the level of pain tolerance was marked on a scale of 1–10, wherein this scale of 1 indicates just noticeable pain/discomfort, 5 indicates moderate pain/discomfort, and 10 indicates intolerant pain/discomfort.
Evaluation of anthropometric measures
The body stature and the body weight of the participants were measured using Martin's anthropometric rod and a properly calibrated weighing machine, respectively. From the anthropometric data, the body mass index (BMI) of the subjects was calculated.
Evaluation of physiological parameters
Heart rates (beats/min) of the subjects were measured during rest and work using a stopwatch. Resting and working blood pressure (mm Hg) were measured with the help of a sphygmomanometer and stethoscope. Resting blood pressure was taken just after 15 min of rest and working blood pressure was taken just after work.
Evaluation of postural stress
The maintenance of working posture and the support of the load is a particular example of static work. The workers' diverse working postures were analysed using the Ovako Working Posture Analysis System (OWAS) and the Rapid Entire Body Assessment (REBA) with the use of digital photography. Later on, stick diagrams were drawn from freeze-frame video records and eventually subjected to analysis. The most frequent posture adopted by the workers was taken into consideration and the risk level of these adopted postures was categorized by OWAS and REBA action categories.
Rapid Upper Limb Assessment (RULA) was used to assess the individual worker's exposure to ergonomic risk factors related to upper extremity MSD, which considers the biomechanical and postural load needs of occupational duties and demands on the neck, trunk, and upper extremities.
Proper statistical methods were used to show various associations between the same subjects of different groups (depending on the age/BMI/working experience, etc.) or between reference groups and working groups. The statistical methods included Student's t-test, two-tailed Chi-square test (in contingency table), and MANOVA. All the data were expressed as mean ± standard deviation, where P < 0.05 was considered a limit of significance or else otherwise stated.
| Results|| |
Most of the carpenters suffered from different MSDs as carpentry activity is too much stressful and repetitive. The work environment is not ergonomically adjusted. All the subjects were categorized into two groups: carpenters (N = 148) and non-carpenters (N = 148). Further carpenters and non-carpenters were categorized into Group A, having more than 10 years of working experience, and Group B, having <10 years of working experience. The number of Group A carpenters was 120 and of Group B was 28. The number of Group A non-carpenters was 137 and the number of Group B non-carpenters was 11. Non-carpenters were from the different working sectors of the same economic group.
[Table 1] depicts the general physical characteristics such as age (years), height (in cm), weight (in kg), body surface area (in cm2), BMI (kg/m2), and work experience (years) of the carpenters as well as non-carpenters when grouped in accordance with their working experience.
|Table 1: Physical characteristics of carpenters and non-carpenters grouped according to their working experience|
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[Table 2] shows the percentage of response to different health problems among the carpenters and referents when grouped following their year of exposure. Both the groups reported that they suffered from various health problems such as respiratory, cardiovascular, gastrointestinal (GI), ear, nose, and throat (ENT) disorders, skin diseases, and others. Carpenters (73.30 %) with more than 10 years of exposure were shown to have the highest rate of respiratory impairment. Also, the percentage of individuals suffering from pain in different body parts was significantly higher (93.30%) among the more experienced group. Referents also suffered from respiratory problems, cardiovascular problems, GI problems, ENT-related disorders, skin diseases, body pain, and other problems, but the complaint was much less.
|Table 2: Prevalence of different health predicaments recorded as percentage response among carpenters and non-carpenters grouped in accordance to their working experience|
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[Table 3] represents the detailed response to the feeling of discomfort in different parts of the body by the carpenters. A significant difference in the response was found among the carpenters across the group as per their experience. A greater percentage of carpenters suffered from lower back pain (93.3%).
|Table 3: Percentage response of the carpenters feeling discomfort at different parts of the body|
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The percentage of carpenters who reported discomfort or pain in their bodies at different periods of the day, i.e. pain felt during or after work and before or after sleep at night, following 24 hours of labour, is reflected in [Table 4]. Significant alterations were found among carpenters who felt maximum discomfort after work and before or after sleep at night across the group. Following this response, the feeling of discomfort by the carpenters during the last 6 months and 12 months was recorded and represented as the percentage of response in tabulated form [Table 5]. Significant variations in discomfort feeling in the neck, right shoulder, right wrist, and lower and upper back were found in accordance with their working experience. The age of the carpenters along with weekly working hours and working intervals significantly alters the status of musculoskeletal associated problems as depicted in [Table 6]. Discomfort feelings at different parts of the body represented as body part discomfort score are depicted in [Figure 1] and tabulated in [Table 7] with detailed statistics. A significant difference of discomfort had been found at the head, shoulder, neck, arm, wrist, lower back, upper back, waist, knee, and ankle among more and less experienced carpenters.
|Figure 1: Discomfort feeling at the different parts of the body represented as BPD score. BPD: Body part discomfort|
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|Table 4: Discomfort felt by the carpenters during different times of a day|
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|Table 5: Percentage response of the trouble at different parts of the body during last 6 months and 12 months|
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|Table 6: Prevalence of musculoskeletal associated problems according to the age, weekly working hours, and working intervals of carpenters|
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|Table 7: Body part discomfort score which measures the discomfort at different parts of the body among the carpenters grouped according to their working experience|
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Year of exposure and weekly working hours were treated as an independent variable to find any association with pain prevalence among the carpenters. There was a statistically significant difference in pain prevalence on years of exposure, but work duration did not yield any significant result as tabulated in [Table 8]a and [Table 8]b.
|Table 8: MANOVA' assessment to test the multivariate sample means (a) Multivariate test on the year of exposure (b) Multivariate test of between the subject's effect|
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Carpenter does adopt the awkward posture and gets exposed to that for a prolonged period for which there exists a need for posture analysis which had been done after proper analysis as depicted in [Figure 2]. The degree of manifestations due to awkward posture had been deduced by the OWAS, REBA, and RULA assessments.
|Figure 2: Working posture analysis by OWAS, REBA, and RULA of the carpenters. OWAS = Ovako working Posture Analysis System, REBA = Rapid Entire Body Assessment, RULA = Rapid upper limb assessment|
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| Discussion|| |
Carpenters suffer from varied occupation-related health problems. Different factors make carpentry at risk to occupational health. The repetitive nature of work, awkward working posture, and primitive tools are the most common factor responsible for occupational health hazards. Most of the carpenters are either illiterate or possess primary level education and also lack of proper training for following ergonomically defined methods needed for making furniture. Many carpenters perform their job early from childhood following family tradition due to lower socioeconomic status. Many carpenters lack basic spatial skills needed for new technological applications though they improve their skills in due course of the apprenticeship.
As observed from our study, the average age of Group A with a mean work experience of 21.50 ± 8.68 years was 43.80 ± 9.23 years, i.e., most of the carpenter workers fall into middle age, and the mean BMI value was 22.86 ± 3.22 kg/m2 for Group A and 22.11 ± 2.2 kg/m2 for Group B with a mean work experience of 6.74 ± 1.84 years, which is lying within normal range. According to Nutritional Trends in India, BMI values of 18.5 kg/m2 to 24.99 kg/m2 are considered normal (Nutritional Trends in India 1993). As observed, the BMI of the carpenters lay in the normal range, which governs the fact that they are not suffering from insufficient nutrition and thus BMI might not be responsible for the development of occupational hazards among them.
The unorganized work environment of the small-scale industry is not healthy for carpenters, and our state's tropical climate influences the environmental condition. In industrial plants, acute as well as chronic exposure to occupational stressors is found to be lethal to the workers and shreds of evidence suggest that there is a strong association between respiratory health problems and certain occupations. Even though certain compounds are known to impact all physiological systems, the lungs are particularly sensitive to airborne risks caused by exposure to wood dust created in sawmills, furniture manufacturing, cabinet building, and carpentry., Exposure to wood dust has been linked to symptoms such as cough, malaise, chest discomfort, dyspnea, and headache in woodworkers. A few studies have looked at the involvement of wood dust in occupational asthma, chronic bronchitis, pneumonitis, respiratory distress, nasopharyngeal cancer, and lung cancer, but the evidence is mixed., It was hereby noted that a higher percentage of the respondents (carpenters) reported respiratory problems (73.3%), followed by GI problems (83.30%) and then skin-related diseases (46.60%), which may be attributed to the fact that they are exposed to wood dust and other volatile substances. The presence of different chemicals used in varnishing, glues, and types of wood might be the possible reasons for the development of skin diseases as was evident from the previous studies which demarcated the presence of isothiazolinones and N-methylol-chloroacetamide in glue, epoxy resins, chromate, rubber chemicals, formaldehyde, teak wood, jacaranda wood, etc., used for carpentry causing allergic contact dermatitis.,
Carpentry involves a wide variety of tasks that are repetitive in nature and the workers have to maintain a constant awkward posture for a prolonged period of time., Carpentry involves the wood collection, and modification to the finished product which is quite laborious, and for which carpenters are exposed to both physical and chemical occupational stressors. It was observed that the carpenters reported a higher prevalence of MSD (93.30%) and subsequent development of discomfort in the various region of the body with the lower back being the most affected area followed by the waist, shoulder, neck, wrist, head, and knee. The pain was reported to be higher after the task they perform and also before and after the sleep which continued for the last 12 months as well. Weekly working hours and working intervals were also involved in influencing the development of MSD. Shreds of evidence suggested that strenuous repetitive working posture had a major impact on the development of MSD as carpentry involves uncomfortable and stressful postures, like working with saw machine, drilling machine, plaining the wood by carpenters' plane, nailing, screw driving causing knee straining, muscular overload affecting shoulder-arm muscular activity thus leading to arm-shoulder-neck disorders,, overexertion injuries resulting from manual materials handling activities and account for the majority of back injuries. Based on the postural analysis, it was clear that the majority of the postures taken by the carpenters were incorrect and required additional investigation and implementation of adjustments. Improper postures involving forwarding bent positions for a prolonged period of time may influence the comprehensive force on the vertebral disks and erector spine muscles and will also aid in the development of MSD and discomfort at different body parts.
| Conclusion|| |
Carpenters suffered from various work-related problems, mainly MSDs because of their working posture. They do suffer from pain in various body parts during working hours and also during the resting phase. By analyzing their working posture, it was observed that some working postures of a carpenter were very stressful because of which they develop the MSD (e.g., spondylitis, neck pain, and back pain), and it was observed that their workplace is not properly arranged and also their working environment is not suitable for their health condition and different working instruments were scattered, which may cause an accident. During scrubbing of the wood and cutting of wood, wood dust arises, which may be the possible reason for the development of various respiratory problems. Other associated operations, such as polishing and pasting, may introduce chemicals into their bodies, causing poisoning. During the use of a drilling machine, the vibration may damage nerves in different parts of the body. Hence, ergonomic interventions are required to improve the quality of life of the carpenter.
Thus, recommendations such as task or job rotation schedule can be implied; proper work-rest schedule to be followed during their work to reduce the strenuous frequency of working in awkward posture and enabling recovery from strain; proper ergonomically designed tools, electrically operated tools, overload sharing techniques must be implemented to reduce the exorbitant force on the workers; Workstations should be constructed with adequate space, ventilation, and illumination in mind, and frequent medical check-ups should be scheduled.
The authors would like to acknowledge all the participants for their kind participation and support.
Financial support and sponsorship
SS acknowledges the partial financial support from PRG and DSTPURSE II of the University of Kalyani to carry out this research work.
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8]