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ISSN : 1598-7248 (Print)
ISSN : 2234-6473 (Online)
Industrial Engineering & Management Systems Vol.18 No.4 pp.609-618
DOI : https://doi.org/10.7232/iems.2019.18.4.609

The Association of Worker Characteristics and Occupational Factors with Musculoskeletal Complaints of Building Construction Workers in Indonesia

Wyke Kusmasari*, Titah Yudhistira, Yassierli
Department of Industrial Engineering and Management, Institut Teknologi Bandung, Bandung, Indonesia
Corresponding Author, E-mail: kusmasari.wyke@gmail.com
May 7, 2019 September 19, 2019 October 18, 2019

ABSTRACT


Construction has been categorized as an industry with a high prevalence of musculoskeletal complaints. Previous studies have found that several risk factors are related to such complaints across industries, but limited evidence exists for construction work. Effective interventions are needed to minimize the risk of musculoskeletal disorders among construction workers. This study involved 33 workers of a building construction project in the campus of Institut Teknologi Bandung. A self-reported questionnaire was utilized to collect data on workers’ musculoskeletal complaints, and the data were then processed using logistic regression. The results showed that shoulder was the body part with the highest prevalence during the last 12 months. Significant associations were found between work hour per day and the prevalence of knee complaint (OR:1.63; 95% CI:1.02-2.63) as well as between race and shoulder complaint in the last 6 months (OR:12; 95% CI:1.17-122.45). Implications of the results are discussed. Further, the findings suggest that work characteristic and occupational factors need to be considered in developing effective interventions to reduce risks of musculoskeletal disorders for construction workers in Indonesia.



초록


    1. INTRODUCTION

    Although a number of research has been done in minimizing risk of work-related musculoskeletal disorders (WMSDs), the outcomes in industry are still not satisfying. It appears that more effective intervention models are needed (Arezes and Serranheira, 2017). Lack of understanding of WMSDs phenomena may affect lack effectiveness of the intervention.

    Musculoskeletal disorders (MSDs) are disorders of the condition of nerves, tendons, muscles, and supporting structures of the human body (Deros et al., 2014). MSDs can be caused by repeated exposure to loading (EU-OSHA, 2007) . In UK during 2016–2017, there are a total of 8.9 million lost working days due to MSDs (HSE, 2017). A total of 79,890 MSDs cases were reported in 2015 in the United States (BLS, 2016). Similar conditions have been reported in developing countries. For example, 23,477 MSDs cases were reported in Colombia in 2005, equal to about 11.6 cases per 10,000 employees (Piedrahita, 2016). In this country, the total estimated cost of MSDs relative to the employee productivity was US$171.7 million, representing of 0.2% of Colombia’s Gross Domestic Product (Piedrahita, 2016). Unfortunately, no similar data is available in Indonesia.

    Musculoskeletal disorders can occur over an extended period. In short term, MSDs are assessed through the prevalence of musculoskeletal complaints. One type of musculoskeletal complaints is low back pain (LBP). It is defined as any “non-traumatic musculoskeletal disorder affecting the low back.” LBP included all back pain, regardless of diagnosis, that was not secondary to another disease or injury cause (Lette et al., 2018). LBP is among the top five injuries among building construction workers (Lette et al., 2018), representing the highest prevalence of musculoskeletal disorders among construction workers in developing country.

    Our previous study found that most of Indonesian construction workers are suffering from elbow, shoulder, and lower back complaints (Kusmasari, 2017). However, the study had a limitation in terms of number of respondent. Another study showed that lower back complaints were also reported by the most construction workers in Malaysia (Deros et al., 2014).

    Some risk factors have been known to affect MSDs in construction workers. Individual, physical, psychosocial, and occupational factors have been substantially associated with the prevalence of MSDs.

    Individual risk factors consist of age, sex, anthropometry, smoking status, strength of physical activity, level of education, years of experience in the workplace, alcohol intake, etc. (Ekpenyong and Inyang, 2014). Overall, musculoskeletal complaints on construction workers have been associated with the following factors: gender (Merlino et al., 2003;Dong et al., 2012), years of experience (Merlino et al., 2003;Ekpenyong and Inyang, 2014;Hanklang et al., 2014), weight, employment status (Ekpenyong and Inyang, 2014), education level (Ekpenyong and Inyang, 2014), smoking status (Ajslev et al., 2015), alcohol intake (Ajslev et al., 2015), body mass index (Ekpenyong and Inyang, 2014;Ajslev et al., 2015;Robroek et al., 2017), age (Ekpenyong and Inyang, 2014;Ajslev et al., 2015;Chakraborty et al., 2018;Moberg et al., 2017). However, previous studies showed different results. Educational level (Moberg et al., 2017), smoking status (Ekpenyong and Inyang, 2014;Alghadir and Anwer, 2015), BMI (Alghadir and Anwer, 2015), age (Welch et al., 2009;Alghadir and Anwer, 2015), marital status (Ekpenyong and Inyang, 2014;Alghadir and Anwer, 2015) and height (Ekpenyong and Inyang, 2014) were not associated with musculoskeletal complaints on construction workers.

    Results pertaining to individual effects as risk factors of specific MSDs on construction workers seem not conclusive. Age (Holmstrom and Engholm, 2003), smoking status (Meo et al., 2013), and physical strength (Neeraja et al., 2014;Moberg et al., 2017) were associated with neck pain. Year of experience (Merlino et al., 2003), physical strength (Moberg et al., 2017), history of shoulder pain (Borstad et al., 2009), smoking status (Meo et al., 2013), and age (Holmstrom and Engholm, 2003) were associated with shoulder/arm pain. Year of experience (Merlino et al., 2003), educational level (Dong et al., 2012), smoking status (Meo et al., 2013), and age (Holmstrom and Engholm, 2003) were significantly associated with back pain. Besides that, age (Holmstrom and Engholm, 2003) and smoking status (Meo et al., 2013) were associated with lower limb pain.

    Physical factors that significantly affect MSDs include movement of body parts that are intense, fast, awkward posture (for example, bending, straightening, grasping, holding, rotating, clenching, and reaching out and arms) (Ekpenyong and Inyang, 2014). Other physical factors include extreme posture, insufficient recovery time, and vibration exposure (Ekpenyong and Inyang, 2014). The physical factors are commonly represented by the presence or absence of awkward postures, awkward movements of the head and arms, works against strength or vibration, manual material handling (MMH), and fast working speed (Ekpenyong and Inyang, 2014, Sobeih et al., 2009). Overall musculoskeletal complaints on construction workers have been significantly associated with manual handling, repetitive movement (Merlino et al., 2003;Borstad et al., 2009), and working in the same position (Merlino et al., 2003), grasping small objects (Merlino et al., 2003), fast work pace (Kusmasari, 2017), high physical workload (Sobeih et al., 2009;Hanklang et al., 2014;Robroek et al., 2017), and awkward postures (Merlino et al., 2003;Ekpenyong and Inyang, 2014;Hanklang et al., 2014;Moberg et al., 2017).

    Previous studies have also looked at specific muscle complaints on construction workers. Work with hands above the shoulders, twisted posture, vibration (Engholm and Holmstrom, 2005), repetitive movement (Neeraja et al., 2014), and manual material handling (Engholm and Holmstrom, 2005;Neeraja et al., 2014) were reported to be associated with neck pain. Kneeling, vibration, and work with hands above the shoulders were associated with shoulder/arm pain (Engholm and Holmstrom, 2005). Working in the same position (Merlino et al., 2003), kneeling, vibration, and work with hands above the shoulders (Engholm and Holmstrom, 2005) were associated with lower limb pain. Working in the same position (Merlino et al., 2003), kneeling, vibration, and work with hands above the shoulders (Engholm and Holmstrom, 2005) were associated with back pain.

    Psychosocial factors include monotonous work, poor social interaction, isolated work environment, pressure to achieve high performance, lack of job control, time pressure, and poor supervisor-employee relations (Ekpenyong and Inyang, 2014). Psychosocial items assessed in their study were latitude of decision, psychosocial demands and mental workload, social support, and work insecurity (Ekpenyong and Inyang, 2014). Psychosocial work demands can also be measured in terms of job control, psychological demands, social support, and job dissatisfaction (Neeraja et al., 2014). Psychosocial factors reflect psychological and social aspects involving the person and / or the surrounding environment (Sobeih et al., 2009). The International Labor Office (ILO) defines psychosocial factors related to work as "interactions between and between work environments, work content, organizational conditions and capacity of workers, needs, culture, extra personal considerations that may, through perception and experience, affect health, performance work and job satisfaction” (Sobeih et al., 2009). In a joint report by the International Labor Organization and World Health Organization (1986), psychosocial factors are defined as aspects of the work environment, additional work environments, and individuals who interact to influence well-being (Salem et al., 2008). A more simple definition is a condition that leads to stress in the workplace, and related health and safety problems (Sobeih et al., 2009).

    Psychosocial factors that cause stress in the workplace can be categorized into: job characteristics, qualitative and quantitative workloads, work environment, working hours, work shifts; roles in the organization, for example, ambiguity of roles, responsibilities of people and equipment; social aspects, worker-supervisory relations, social support; career development for example, job insecurity, promotion, work wages; and organizational factors, for example, management style, policy, participation in decision making (Sobeih et al., 2009).

    In this study, psychosocial factors are related to work and work environment, as well as with the characteristics of individual workers. Factors related to work and work environment include lack of variations in work assignment, lack of control, too heavy work responsibilities, psychologically demanding work, poor supervision support, poor coworkers’ support, and poor information (Holmstrom and Engholm, 2003). Interestingly, psychological demands and job dissatisfaction were significantly associated with neck, shoulder/arm, and back pain (Neeraja et al., 2014).

    Previous studies reported that musculoskeletal complaints on construction workers have been significantly associated with the following occupational factors: work hours per week, the use of personal protective equipment (Rosecrance et al., 2002;Borstad et al., 2009). More specifically, shift work (Borstad et al., 2009), job type (Rosecrance et al., 2002) and hot or cold environments (Rosecrance et al., 2002;Borstad et al., 2009) were significantly associated with shoulder/arm pain.

    However, the associations of worker characteristics and occupational factors with MSDs among construction workers in developing countries are not clearly characterized. The risk of MSDs among construction workers varies among nations (Ekpenyong and Inyang, 2014). No previous study has concluded the association of risk factors with the prevalence of MSDs in Indonesia. Thus, this study aimed to investigate the associations between individual and occupational risk factors with the prevalence of MSDs among Indonesian construction workers. We determined the odds between individual characteristics and musculoskeletal complaints among the workers studied, as well as the odds between the participants’ occupational factors and musculoskeletal complaints. We hope the results of this study will be considered in developing ergonomic interventions to prevent MSDs among construction workers in Indonesia.

    2. SUBJECTS AND METHODS

    2.1 Study Preparation

    This study was conducted in March 2017. Respondents were construction workers from local construction companies in Indonesia. The study required a letter for permission from the project leader and safety supervisors. Data were collected during a safety talk at the beginning of workday. Respondents were given the souvenirs as the compensation.

    2.2 Study Population

    Thirty-three construction workers participated in the study. All of them were males. Table 1 provides a summary of respondents’ demographic data. Respondents were recruited from different jobs: safety (1), plumbing (1), finishing (3), land share (1), water tunnel (2), gardening (1), tiling (2), concrete work (3), interior finishing (4), electrical work (6), apprenticing (1), welding (2), and others (6). In term of their races, the respondents consisted of Sundanese, Javanese, and Betawi, aged between 18 and 56 years old.

    2.3 Questionnaire

    The respondents were given a set of questionnaire that consisted of two sections. Section A focused on sociodemographic data and working conditions, while Section B gathered information about self-reported musculoskeletal complaints.

    The sociodemographic section requested information about individual characteristics (age, gender, height, weight, educational status, ethnic group) and occupational information (name of the current job, work hours, shift work). The self-reported musculoskeletal complaint questionnaire was adapted from the standardized Nordic questionnaire (Kuorinka et al., 1987;Widanarko et al., 2014). There were three main questions: (1) Have you at any time during the last 12 months had any trouble (such as aches, pains, discomfort, numbness or fatigue) in this body region? (2) Have you at any time during the last 6 months had any trouble (such as aches, pains, discomfort, numbness or fatigue) in this body region? (3) Have you at any time during the last 7 days had any trouble (such as aches, pains, discomfort, numbness or fatigue) in this body region?

    2.4 Statistical Analysis

    Prevalence of MSDs for each part of the body was determined by dividing the number of “yes” with the total number of participants (Deros et al., 2014). The data were analyzed using Microsoft Excel for Mac Version 15.24. The prevalence of musculoskeletal complaints were asked in three conditions: during the last 7 days, the last 6 month and the last 12 months.

    We used STATA/IC software version 15.0 to calculate logistic regression. Odds ratio were computed for each association among workers characteristics, occupational factors and musculoskeletal complaints. Musculoskeletal complaints were recorded in terms of frequency and percentage (%). It should be noted that odds ratios (OR) were commonly reported in the medical literature as a measure of association between exposure and outcome (Viera, 2008).

    3. RESULTS

    3.1 Prevalence of Musculoskeletal Complaints

    The prevalence of musculoskeletal complaints in terms of percentage complaints during the last 12 months reported by the respondents as the following: shoulders (64.52%), lower back (61.54%), upper back (53.57%), wrists/hands (53.33%), neck (50%), ankle/leg (46.43%), knees (44.44%), hips/thighs (43.33%), and elbow (40%). The prevalence of musculoskeletal complaints in terms of percentage complaints during the last 6 months as the follows: wrists/hands (47.83%), lower back (36.36%), hips/thighs (32%), knees (31.82%), neck (28.57%), upper back (28%), elbow (28%), ankle/leg (26.09%), and shoulders (25%). The prevalence of musculoskeletal complaints during the last 7 days: lower back (52.38%), wrists/hands (41.67%), upper back (39.13%), shoulders (38.46%), knees (38.46%), neck (35.71%), ankle/leg (33.33%), elbow (29.17%), and hips/thighs (28%).

    3.2 Association between Individual Characteristics and Musculoskeletal Complaints

    Table 2 shows the association between individual characteristics and musculoskeletal complaints during the last 12 months.

    No association was found between weight, BMI, year of experience, work hours/day, right-handed, shift work, race, and type of job with musculoskeletal complaint. However, based on their p-value, some associations are approaching significant (p<0.1). This result was found for the associations of age with wrist complaint and height with wrist-knee complaint.

    Table 3 shows the association between individual characteristics and musculoskeletal complaints during the last 6 months. No association was found between BMI, year of experience, right-handed, shift work, race, and type of job with musculoskeletal complaint. However, a significant association was identified between race and shoulders complaints (p<0.05). Work hours per day was also associated with knee complaints (p<0.05). Some findings with approaching significant, at p<0.1, include the associations of age with wrist complaint, height with elbow complaint, weight associated with lower back complaint, and year of experience with lower back complaint.

    Table 4 shows the association between individual characteristics and musculoskeletal complaints during the last 7 days. No significant association was found between age, height, weight, BMI, year of experience, work hours/day, right-handed, shift work, race, and type of job with musculoskeletal complaint. Some findings with approaching significant, at p<0.1, include the associations of height with elbow complaint, work hours/day with upper back and knee complaint, and right-handed with ankle complaint.

    4. DISCUSSION

    4.1 Prevalence of Musculoskeletal Complaints

    This study aimed to investigate the prevalence and risk factors of musculoskeletal complaints among construction workers. More specifically, we are interested in finding out the associations between individual and occupational factors with musculoskeletal complaints on specific body parts. We found that the complaint was the highest for shoulders reported during the last 12-months prevalence.

    Interestingly, our results are able to provide broader insight of MSDs risk factors compared to previous studies. Previous studies found that lower back was the most reported complaints in construction workers (Holmstrom and Engholm, 2003;Merlino et al., 2003;Deros et al., 2014;Alghadir and Anwer, 2015), followed by wrist (Merlino et al., 2003), knee (Alghadir and Anwer, 2015), and shoulder complaints (Deros et al., 2014). This conflicting result can be caused by the differences in characteristics of each type of construction work carried out by the respondents, such as repetitive movement, poor working position, and vibration intensity (Deros et al., 2014).

    Participants in this study were dominated by finishing workers so that they might exposed by lower physical efforts. Therefore, differences in complaints that are most felt by construction workers can occur. On the other side, other researchers reported the prevalence of musculoskeletal complaints were at lower back (68%), knee (68%), wrist (63%), shoulder (55.6%), neck (28.3%), upper back (13.3%), elbow (10%), thighs (8.3%), ankles (6.3%), and hands (2.4%) (Yassierli et al., 2009;Alghadir and Anwer, 2015;Eaves et al., 2016).

    4.2 Worker Characteristics

    The results of the present study showed that there was significant association (p<0.05) between worker characteristics (race) with musculoskeletal complaints. It is showed that race was significantly associated with shoulders complaints. Another previous study reported similar association (Ekpenyong and Inyang, 2014). Certain race and low education status have higher odds to develop musculoskeletal disorders (Ekpenyong and Inyang, 2014). The effect of race is rarely studied in relation to musculoskeletal complaints. So far there is no literature that discusses the difference among the biggest ethnics in Indonesia, such as: Sundanese, Javanese, or Betawi ethnic against the MSDs risk level. This becomes one of the future research opportunities related to MSDs in Indonesia.

    BMI was not significantly associated with musculoskeletal complaints . This result is similar to other study (Alghadir and Anwer, 2015). Nevertheless, other study showed a significant association (Ekpenyong and Inyang, 2014). Construction workers with high BMI had more than twice the odds for musculoskeletal disorders (Ekpenyong and Inyang, 2014). These conflicting results suggest a need for further research about the association between BMI and musculoskeletal complaints. The body mass index can worsen pain due to increased mechanical tensions and joint damage in workers with arthritis (Ekpenyong and Inyang, 2014).

    4.3 Occupational Factors

    The present results showed that there was significant association (p<0.05) between occupational factors (work hours per day) with musculoskeletal complaints. This study showed that working hours per day significantly associated with the prevalence of knee complaints in the last 7 days and 6 months. Work hours per day was also associated with the prevalence of upper back complaints in the last 7 days. Previous research show that women rebar workers with prolonged working hours had 7.6 higher MSDs risk compared with workers who did not have prolonged working hours (Hanklang et al., 2014). In contrast, another study showed that construction workers who worked more than 8 hours/day have not significant difference of musculoskeletal complaints than workers worked less than 8 hours/day (Alghadir and Anwer, 2015).

    However, work hour/day was not found to affect MSDs (Chakraborty et al., 2018). This is due to limited rest and recovery time may increase the risk of MSDs. Additionally, shift work was not significantly associated with musculoskeletal complaints. No previous study showed any association between shift work and musculoskeletal complaints. Shift work might have an effect because construction workers who worked at night tend to experience increased fatigue as a surrogate measure of musculoskeletal disorders.

    4.4 Factors with Approaching Significant Effect

    There are some risk factors approaching significant with p<0.01. Age seemed to be associated with wrist complaint in the last 6 and 12 months. Weight appeared to be associated with lower back complaint in the last 6 months. Height seemed to be associated with elbow complaint in the last 7 days and 6 months, then with wrist and knee complaint in the last 12 months. Year of experience appeared to be associated with lower back complaint in the last 6 months. Right-handed seemed to be associated with ankle complaint in the last 7 days. Work hours per day seemed to be associated with upper back and knee complaint in the last 7 days.

    Age seemed to be associated with wrist complaint in the last 6 and 12 months. Similarly, other study showed a positive significant association between age and musculoskeletal disorders (Ekpenyong and Inyang, 2014;Chakraborty et al., 2018). Older workers had 2.35 times the odds for incidental musculoskeletal disorders than younger construction workers (Ekpenyong and Inyang, 2014). A previous study showed that older workers (>50 years) reported less complaints that younger workers (Eaves et al., 2016). This phenomenon called ‘macho’ culture that older workers are less likely reported the complaints because of fear from supervisor judgement (Eaves et al., 2016). Older construction workers have a high chance of the prevalence of musculoskeletal disorders (Ekpenyong and Inyang, 2014). Different results are reported by other studies. Those workers aged between 39-48 years have a risk of 4 times having neck pain compared to workers who have ages 48-58 years and more than 59 years (Shan et al., 2012).

    Weight seemed to be associated with lower back complaint in the last 6 months. If this is true, weight must be considered as one risk factor of musculoskeletal complaints. Any preventive program should be taken to minimize the risk of musculoskeletal disorders due to over body weight.

    Height seemed to be associated with elbow complaint in the last 7 days and 6 months, as well as with wrist and knee complaint in the last 12 months. Likewise, other study showed height was also predictive for shoulder complaints (Borstad et al., 2009). The effect of height on MSDs is still unknown. Shorter workers more likely to develop shoulder complaints (Borstad et al., 2009). This can be caused by shorter workers producing greater muscle tensions to do the same overhead work (Borstad et al., 2009). These findings suggest that shorter workers should utilize supporting tools like scaffolding to minimize musculoskeletal efforts in shoulder, elbow, or wrist.

    Year of experience seemed to be associated with lower back complaint in the last 6 months. Supported by the results from other study, more experience construction workers had more twice the odds for musculoskeletal disorders (Ekpenyong and Inyang, 2014). Workers who have worked for more than 5 years have a higher prevalence of musculoskeletal complaints (Alghadir and Anwer, 2015). Musculoskeletal complaints prevalence are about 33% for workers who work less than 5 years, 40% for 6-10 years, and 84% for 30 years work experience (Alghadir and Anwer, 2015). These results showed a linear association between year of experience and musculoskeletal complaints. Thus, a specific intervention need for minimize musculoskeletal complaints as the years of work experience increase. It is possible that more experienced workers are more exposed to work risks at work because familiar work processes do not seem to be a protective factor (Hembecker et al., 2017). The relationship between the year of experience and complaints on the knee is getting stronger along with the increase in the length of work (Merlino et al., 2003). Figure 1 demonstrates the overall findings of significant (p<0.05) and approaching significant (p<0.1) that are associated with musculoskeletal complaints.

    4.5 Further Research

    This study is only a case-study with a relatively limited of participants. To obtain a generalizable conclusion for the Indonesian construction worker population, more respondents are needed in subsequent research.

    However, this research is still relevant because it only provides a descriptive description of association risk factors with musculoskeletal disorders through odds ratios. In addition, other risk factors such as physical, psychosocial, and environmental needs to be confirmed in relation to MSDs in construction workers in Indonesia.

    5. CONCLUSION

    In conclusion, the highest prevalence of musculoskeletal complaints in the construction was reported at shoulders. Workers’ race, age, height, weight, year of experience, and work hours per day may increase the level of risk of MSDs in construction workers. Further research will be conducted with a larger number of participants. Further research should also consider other risk factors besides individuals such as physical and psychosocial relationships with MSDs of construction workers in Indonesia.

    6. ETHICAL CONSIDERATIONS

    Ethical issues (Including plagiarism, Informed Consent, double publication and/or submission, redundancy, etc.) have been completely observed by the authors.

    ACKNOWLEDGEMENTS

    The study was funded by Indonesia Endowment Fund for Education [LPDP]-Ministry of Finance trough doctoral program scholarship.

    Figure

    IEMS-18-4-609_F1.gif

    Associations of worker characteristics and occupational factors with musculoskeletal complaints.

    Table

    Demographic data of the respondents

    Associations of worker characteristics and occupational factors with the prevalence of musculoskeletal complaints in last 12 months (OR; 95% CI)

    Associations of worker characteristics and occupational factors with the prevalence of musculoskeletal complaints in last 6 months (OR; 95% CI)

    Association worker characteristics, occupational factors, and prevalence of musculoskeletal complaints in last 7 days (OR; 95% CI)

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