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 Table of Contents  
ORIGINAL ARTICLE
Year : 2016  |  Volume : 15  |  Issue : 1  |  Page : 7-13

Work-related musculoskeletal disorders and ergonomic stressors among direct and nondirect contact health care workers from a Nigerian tertiary health facility


1 Department of Physiotherapy, Olabisi Onabanjo University Teaching Hospital, Sagamu, Nigeria
2 Department of Community Medicine and Primary Care, Olabisi Onabanjo University, Sagamu, Nigeria

Date of Web Publication10-Jun-2016

Correspondence Address:
Olufemi O Oyewole
Department of Physiotherapy, Olabisi Onabanjo University Teaching Hospital, PMB 2001, Sagamu
Nigeria
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/2384-5589.183891

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  Abstract 


Background: Work-related musculoskeletal disorders (WRMDs) among health care workers have increased with little information on ergonomic stressors' exposure. Therefore, the exposure of health care workers to ergonomic stressors and the consequent WRMDs were investigated. Materials and Methods: The descriptive cross-sectional study involved 279 stratified participants from various departments of Olabisi Onabanjo University Teaching Hospital. Standardized Nordic and adapted European Foundation questionnaires were used to obtain data on musculoskeletal pain and ergonomic stressors. The data were analyzed with Statistical Package for the Social Sciences (SPSS) using descriptive and inferential statistics. Results: About 48% of the participants reported WRMDs in at least one part of the body during the 12 months preceding the study while 22.2% reported WRMDs in the last 7days. During the preceding 12 months and the last 7 days, the lower back was the most common site of disorders (29.4% and 9.7%, respectively) while the elbow joint was the least affected site. About 49.7% and 42.7% of the clinical staff and nonclinical staff, respectively, reported WRMDs in the last 12 months while 22.3% versus 22.0% reported WRMDs in the last 7 days. Female participants had a higher prevalence of WRMDs but significant gender difference existed for point prevalence only. A majority of the participants (65.8%) were exposed to 11 or more risk factors. There was a significant association between both 12-month and point prevalences of WRMDs on the one hand and exposure to painful tiring positions on the other. Conclusions: The prevalence of WRMDs was high among health care workers with the lower back being the most frequently affected body region. Work involving painful/tiring positions was the most common ergonomic risk factor associated with WRMDs.

Keywords: Ergonomic stressors, health care workers, musculoskeletal disorders, occupational health, prevalence


How to cite this article:
Oyewole OO, Adeniyi EA, Ajayi BF, Olajitan AA, Oritogun KS. Work-related musculoskeletal disorders and ergonomic stressors among direct and nondirect contact health care workers from a Nigerian tertiary health facility. Afr J Med Health Sci 2016;15:7-13

How to cite this URL:
Oyewole OO, Adeniyi EA, Ajayi BF, Olajitan AA, Oritogun KS. Work-related musculoskeletal disorders and ergonomic stressors among direct and nondirect contact health care workers from a Nigerian tertiary health facility. Afr J Med Health Sci [serial online] 2016 [cited 2019 Jan 19];15:7-13. Available from: http://www.ajmhs.org/text.asp?2016/15/1/7/183891




  Introduction Top


Musculoskeletal disorders affecting many occupations are generally seen as a consequence of a combination of factors, which can include poor posture, highly repetitive movements, forceful hand application, hand-arm vibration, direct mechanical pressure on body tissues, cold work environments, how work is organized, and how workers perceive the work organization.[1],[2],[3],[4],[5],[6],[7] In addition, psychosocial factors such as work demands, job control, job content, and social support have been implicated for increased report of work-related musculoskeletal disorders (WRMDs).[1] Faulty ergonomics workstation has been noted to increase the prevalence of musculoskeletal disorders.[8] This results in the experience of cumulative trauma injuries by those workers who are exposed to such workstations. The factors that contribute to the cumulative trauma injuries in the office are repetitions, sustained static exertions, forceful exertions, localized contact stresses, and posture.[8]

Previous studies have reported increased prevalence of WRMDs in health care workers.[1],[2],[3],[4],[5],[6],[9],[10] In India, 61% prevalence was reported for dentists, 37% for surgeons, and 20% for physicians [2] while 85% and 89.1% were reported for Saudi Arabian and Iranian nurses, respectively.[1],[4] In Nigeria, WRMDs prevalence of 91.3% and 78% was reported among physiotherapists [9] and nurses,[10] respectively. Well-designed workstations have been shown to decrease WRMDs.[8],[9],[10],[11],[12],[13]

Although previous studies have reported increased WRMDs among health care workers, these studies focused majorly on professions that have direct contact with patients.[1],[2],[3],[4],[5],[6],[9],[10] In Nigeria, little is known about WRMDs in health care workers who have nondirect contact with patients and the ergonomic risk factors they are exposed to. Therefore, the exposure of health care workers to ergonomics stressors and the resulting WRMDs they suffer were investigated in this study.


  Materials and Methods Top


The cross-sectional survey was approved by the Research Ethics Committee of Olabisi Onabanjo University Teaching Hospital, Nigeria and the participants gave their informed consents. The institution consists of 893 staff, out of which 664 (74.4%) were clinical staff. This study involved 279 (31.2%) participants from various departments of the institution using stratified sampling technique. The sample was recruited proportionately to represent each of the 12 departments. One hundred and thirty-three (69.2%) evaluated workers belonged to the clinical staff and 82 (29.4%) belonged to the nonclinical staff. Prior to data collection, a standard equation was used to determine the sample size.[14] The calculated minimum sample size was determined to be 278 to power the sample study.

Description of the instrument

Standardized Nordic questionnaire for analysis of musculoskeletal symptoms [15]

The questionnaire comprised forced choice questions and it was self-administered.

It consisted of two sections. Section 1: A general questionnaire of 40 forced-choice items identifying areas of the body causing musculoskeletal problems. Completion was aided by a body map to indicate nine symptom sites, which were the neck, shoulders, upper back, elbows, lower back, wrists/hands, hips/thighs, knees, and ankles/feet. Respondents were asked if they had any musculoskeletal trouble in the last 12 months and last 7 days, which prevented normal activity. Section 2: Additional questions relating to the neck, the shoulders, and the lower back provided further details of relevant issues. Twenty-five forced-choice questions elicited any accident affecting each area, functional impact at home and work (change of job or duties), duration of the problem, assessment by a health care professional, and musculoskeletal problems in the last 7 days. The reliability and validity of this questionnaire have been shown to be acceptable.[15]

Adapted European foundation questionnaire

The questionnaire contained questions to elicit ergonomic stressors and nature of work and it was self-administered. The questionnaire was in two parts. Part 1 asked information about the demography and nature of work or settings while part 2 elicited questions on ergonomic stressors. Part 2 of the questionnaire was rated on a 5-point ordinal scale in reverse order (this was reversed during the computation of data). This questionnaire has been used repeatedly by the European Foundation for the improvement of living and working conditions in its surveys. The validity of the questionnaire was judged to be acceptable.[16]

Data analysis

Statistical analyses were performed using Statistical Package for Social Sciences (SPSS) for Windows version 16.0 (SPSS, Chicago, IL, USA). Data were summarized using frequency, percentage, and graphs. Inferential statistic of chi-square test was used to determine the association between musculoskeletal pain and ergonomics stressors. Mann-Whitney U test was used to compare the prevalence of musculoskeletal pain in male and female workers. The level of significance was set at P = 0.05.


  Results Top


Two hundred and seventy-nine participants returned the questionnaire out of 320 questionnaires that were sent out; 166 (59.5%) questionnaires were from females and 78 (27.2%) were from males. Thirty-nine (13.3%) participants did not indicate their sex. A majority of the participants (69.2%) were clinical staff with 11.9 ± 8.8 years of working experience.

Reports of prevalence of work-related musculoskeletal disorders

About 47.7% (133) of the participants reported WRMDs in at least one part of the body during the 12 months preceding the study while 22.2% (62) reported WRMDs in the last 7 days. About 14.3% and 11.5% reported WRMDs in only one body region in the last 12 months and 7 days, respectively, while 15.1% versus 5% and 18.3% versus 5.7% reported WRMDs in two and three or more body regions in the last 12 months and 7 days, respectively. The lower back was the most common site of WRMDs (29.4% and 9.7%) while the elbow joint was the least affected joint for both 12-month and point prevalences, respectively [Figure 1]. When the WRMDs were adjusted for professions, 49.7% and 42.7% of the clinical and nonclinical staff, respectively, reported WRMDs in the last 12 months while 22.3% and 22.0% of the clinical and nonclinical staff, respectively, reported WRMDs in the last 7 days. The distribution of disorders in the body segment when adjusted for professions followed the same pattern with little difference [Figure 2]. The neck [22 (26.8%) patients] and knee joint [7 (8.5%) patients] were the most affected body parts among nonclinical staff for 12-month and point prevalences, respectively, while the elbow was the least affected for both 12-month and 7-day prevalence rates. The female participants had a higher prevalence of WRMDs but a significant gender difference was found for point prevalence only. The clinical staff also demonstrated a higher prevalence of WRMDs than the nonclinical staff though the difference was not statistically significant [Table 1]. Working experience was significantly associated with WRMDs in the preceding 12 months (χ2 = 10.42, P = 0.01).
Figure 1: Point and 12-months prevalences (%) of musculoskeletal disorders

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Figure 2: Point and 12-month prevalences (%) of musculoskeletal disorders by profession

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Table 1: Gender and profession difference in WRMDs

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Ergonomics risk factors

One hundred and eighty-four (65.8%) were exposed to 11 or more risk factors [Figure 3] while four were not exposed to any ergonomic risk. “Work involves dealing directly with people who are not employees at your workplace” and “painful tiring position” were the highest risk factors the participants were exposed to while “exposure to radiation such as x-rays, radioactive radiation, welding light, and laser beams” was the least [Table 2].
Figure 3: Prevalence of ergonomic risks exposure

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Table 2: Frequency distribution of ergonomic risk factors exposed to by the participants

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Association between work-related musculoskeletal disorders and ergonomic risk stressors

For each ergonomic risk factor, the responses of the participants were dichotomized into categories of “no risk” (1 and 2) and “at risk” (3 to 5). Chi-square test was employed to determine the association between the WRMDs and ergonomic risk factors [Table 3]. There was a significant association between both 12-month and point prevalences of WRMDs on the one hand and exposure to painful tiring positions on the other.
Table 3: Association between prevalence of work-related musculoskeletal disorders and ergonomic risk factors

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  Discussion Top


One hundred and thirty-three (48%) participants reported WRMDs in at least one part of the body during the 12 months preceding the study while 62 (22.2%) participants reported WRMDs in the last 7 days. These prevalence rates were low in comparison with previous studies from Nigeria, which reported a prevalence of 78-91.3% in the preceding 12 months and 66.1% in the last 7 days.[9],[10] The differences might have been be due to the fact that the present study assessed WRMDs in all health care workers (including those in “direct and nondirect contact” with patients) while those previous studies from Nigeria assessed only health care workers who were in direct contact with patients. However, clinical staff reported higher values of WRMDs in the present study. Generally, studies have shown that musculoskeletal problems are particularly common in health care workers who are in direct contact with patients.[9],[10],[17],[18],[19],[20]

In the present study, lower back was the most common reported region of affectation of WRMDs. This finding is consistent with those of previous studies that have overwhelmingly implicated the lower back as the body part most commonly affected by WRMDs among health care workers.[9],[10],[18],[21] Work-related lower back pain ranged between 26% and 70% internationally.[9],[10],[17],[18],[19],[20] This finding may be a further reflection of the overall picture of the poor conditions of practice that may cause a high prevalence of WRMDs among Nigerian health care workers.

This study indicated significant gender difference in the reported WRMDs among health care workers with female staff having higher prevalence than their male counterparts. The findings from this study is consistent with reports from previous related studies, which implicated the female gender as a potential risk factor for the occurrence of WRMDs.[9],[22] Despite the fact that previous studies have shown men to be more exposed to risk factors than women, the latter experienced increased WRMDs.[23],[24] Some authors relate this difference to a lesser muscle tone and a higher incidence of osteoporosis among women [22] or to biological or psychological differences between the women and men as well as different extraprofessional contexts among the women and men [25] while others attribute it to the fact that women do have a higher prevalence than men for many upper extremity musculoskeletal disorders, even after controlling cofounders such as age or work factors.[9] It is likely from the present study that the differences could have been due to work involving painful/tiring position ergonomic risk factor exposed to by the female staff, which was highly associated with WRMDs. A previous population-based study have reported that women were more likely to report awkward or tiring positions compared with men with the same occupation.[26]

The result of this study also showed that working experience was significantly associated with WRMDs in the preceding 12 months. This is consistent with the result from a previous study that indicated that the relative risk of WRMDs is about four times among nurses with greater than 20 years of clinical experience as in those with 11-20 years.[10] It has also been reported that full-time direct patient care occupations have a greater risk of injury compared to part-time and casual workers within the health care sector.[27]

A majority (65.8%) of the participants in the present study were exposed to 11 or more ergonomic risk factors. This may be a reflection of the conditions under which health care workers practice in Nigeria. Practice in Nigeria, similar to many other developing countries, is largely bedeviled by unwholesome work settings, understaffing, and lack of appropriate equipment. This may explain the high incidence of WRMDs in this population. It has been reported that nurses who had higher ergonomic risk factors on the American National Standards Institute (ANSI) Z-365 checklist reported increased WRMDs.[28] It will be of benefit to the staff and employers if adequate steps can be taken to minimize these risk factors in the workplace. Some of these risks require simple education to avoid them. From the present data, it is suggested that high temperature and heat/cold were associated with the report of WRMDs. This is not surprising in poor, unwholesome work settings in the tropical (hot climate condition) regions such as Nigeria where these risks are poorly controlled and access to cooling methods are limited due to epileptic power supply. It has been suggested that workers and employers regularly review the potential impacts of heat on workers' health and productivity in order to minimize excessive heat exposure in the workplace.[29] In addition, short-term remedies such as easy and safe access to water and toilet facilities, regimented rest/drink breaks, appropriate clothing, personal cooling techniques, and equipment can alleviate heat strain.[29]

Work involving painful/tiring position was the highest significant ergonomic risk factor associated with WRMDs. Information and education about WRMDs based on biopsychosocial principles and physical exercise have shown that modest results resolve this menace.[30] Daily work planning has been suggested to allow a break for the alternating muscle groups in order to maintain productive work.[22] The data from this study also suggested that the ergonomic risks “work involves working to tight deadlines” and “work involves dealing directly with people who are not employees at your workplace” were significantly associated with WRMDs. It is likely that the pressure of meeting the deadline and satisfying the clients may be responsible for an increased report of WRMDs.

Despite the heterogeneous tasks performed by these health care workers (clinical staff and nonclinical staff), this study suggests that nonpatient care occupations (i.e., nonclinical staff) also sustain an increased risk for WRMDs. These data suggested that the same trend of risk exposure and pattern of reported WRMDs as in the clinical staff (direct patient care occupations) were observed among the nonclinical staff. It is not clear why the same risk exposure was observed in the present data. It might be that unwholesome work setting characteristics of developing nations such as Nigeria made the risk more pronounced in both groups. As such, prevention effort should be directed to both clinical staff and nonclinical staff. The multifactorial nature of WRMDs must be borne in mind in order to adequately prevent/reduce this menace. In addition, a systematic approach to ergonomic hazard identification, quantification, and control implementation in conjunction with the requirements to establish an ergonomic process at each workstation may be effective in reducing the risk of musculoskeletal diseases and acute injury outcomes among health care workers.[31] Identifying workplace physical ergonomic hazards and workers who are exposed are a crucial first step in mitigating these exposures because ergonomic hazards vary with occupation.[31]


  Conclusion Top


Both clinical staff and nonclinical staff have a similar prevalence of WRMDs. Work involving painful/tiring position was the highest significant ergonomic risk factor associated with WRMDs. There is a need for ergonomic hazard identification and control implementation among these health care workers to reduce the incidence of WRMDs.

Acknowledgement

We wish to acknowledge Dr. Adegoke BOA and Dr. Ayanniyi O, Department of Physiotherapy, University of Ibadan for their contributions and suggestions, and for reading the manuscript. We appreciate the entire staff members of the Physiotherapy Department, Olabisi Onabanjo University Teaching Hospital, Sagamu, Ogun State, Nigeria for their assistance in data collection.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 
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