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 Table of Contents  
ORIGINAL ARTICLE
Year : 2015  |  Volume : 3  |  Issue : 1  |  Page : 18-23

Patterns of occurrence of work-related musculoskeletal disorders and its correlation with ergonomic hazards among health care professionals


1 Department of Medical Rehabilitation, College of Medical Rehabilitation, University of Maiduguri, Maiduguri, Borno, Nigeria
2 Department of Physiotherapy, University of Maiduguri Teaching Hospital, Maiduguri, Borno, Nigeria

Date of Web Publication4-Jun-2015

Correspondence Address:
Sokunbi O Ganiyu
Department of Medical Rehabilitation, College of Medical Sciences, University of Maiduguri, PMB 1069, Maiduguri, Borno
Nigeria
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/2348-0149.158153

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  Abstract 

Background: Health care professionals are commonly identified as being at risk for work-related musculoskeletal disorders (WMSDs) from patient handling and from providing direct care during the course of a patient's stay in the hospital. However, the pattern of occurrence of WMSDs and its relationship with ergonomic hazards among health care professionals has not been widely reported. Objective: The aim of this study was to determine the pattern of WMSDs and its relationship with ergonomic hazard among health care professional who work in a Teaching Hospital in North Eastern Nigeria. Materials and Methods: A cross-sectional study conducted among Dentists, Nurses, Physicians and physiotherapists working at the University of Maiduguri Teaching Hospital. Different combinations of validated and standardized questionnaires were used for collecting data on pattern of WMSDs and ergonomic hazards among the health care professionals. Descriptive (mean, standard deviation and percentages) and inferential (Chi-square test and logistic regression analysis) statistics were used to analyse data. Alpha level was set at P < 0.05. Results: A total of 151 of 162 questionnaires were completed and returned and used for data analysis. The patterns of WMSDs showed higher occurrence among nurses (84.5%) and physiotherapists (83.3%) than physicians (25.3%) and dentist (45.4%). Low back pain was the most complaint (71.6%) among health care professionals followed by shoulder (46.8%) and then neck (42.2%). The upper back (14.7%) and the elbow (8.3%) were the less affected. Prolonged sitting and standing and working in an awkward posture were most common ergonomic hazards among participants. Multiple regression analysis reported statistically significant relationship between all areas of WMSDs and ergonomic hazards identified (P < 0.05). Conclusion: Occurrence of WMSDs among health care professionals was much higher among physiotherapist and nurses than physicians and dentists. Lower back, neck and shoulder were the three most reported WMSDs areas. Work-related ergonomic hazards showed relationship with WMSDs.

Keywords: Ergonomic hazards, health care professional, work-related disorders


How to cite this article:
Ganiyu SO, Olabode JA, Stanley MM, Muhammad I. Patterns of occurrence of work-related musculoskeletal disorders and its correlation with ergonomic hazards among health care professionals. Niger J Exp Clin Biosci 2015;3:18-23

How to cite this URL:
Ganiyu SO, Olabode JA, Stanley MM, Muhammad I. Patterns of occurrence of work-related musculoskeletal disorders and its correlation with ergonomic hazards among health care professionals. Niger J Exp Clin Biosci [serial online] 2015 [cited 2017 Jun 23];3:18-23. Available from: http://www.njecbonline.org/text.asp?2015/3/1/18/158153


  Introduction Top


Work-related musculoskeletal disorders (WMSDs) are a group of syndromes characterized by soft tissue discomfort caused or aggravated by workplace exposures. [1] It is often characterized with pain and discomfort in the muscles, ligaments, tendons, bursa, joint capsules and bone lasting more than 3 days [1] Health care work is known as a high-risk job for WMSDs [1],[2],[3] It is estimated that almost one-third of all cases of sick leave among health care workers are related to WMSDs. [4] Back, neck, shoulder, and knee problems are the most common complaints among medical, dental, and nursing students [5],[6],[7],[8] but it is also more common in other anatomical areas of the body such as the elbow, wrist and hand. Studies of WMSDs among health care providers have mainly focused on dentists, physiotherapists, and nurses [9],[10],[11],[12] , whereas WMSDs occur almost at the same scale among other health care workers. WMSDs are related to labor-intensive tasks, manual handling, repetitive movements, static work postures and adopting an awkward work posture. At work, static muscle loading may occur because of prolonged awkward postures or the need to stabilize or manipulate tools or controls. WMSDs may also be induced by concentration or working faster than a comfortable pace. [13] Other predisposing factors to WMSDs include genetic predisposition, mental stress, physical conditioning, age and obesity, etc. Diffuse pain and discomfort has been shown to arise from the maintenance of extreme flexion postures, a posture similar to that commonly adopted at work. Static muscle loading leads to more rapid fatigue than dynamic work due to simultaneous constriction of the circulation with increased demands by the muscle for oxygen and nutrients as well as the need to disperse waste product resulting from muscle activity [13] Ultimately, these may lead to restriction of job duties, loss of work time and change to another job and total career change. Studies have been carried out on the prevalence of WMSDs among health care professionals [14],[15],[16] These studies reported high prevalence of WMSDs among nurses and physiotherapists. The prevalence of musculoskeletal complaints among physicians was low, less than other health care workers, but similar to those reported in the general population. [17]

In recent time, the predominant threat, attack and security challenges in North-eastern part of Nigeria would have had its consequences on pattern of injury among the residents in these parts of the country. These development would have in no doubt posed a great challenges and increasing work pressure among health care professionals who have to look after the victims of the attack especially in a tertiary health care facilities, University Maiduguri Teaching Hospital located at the center of Maiduguri Metropolis. It is also possible that the ongoing security challenges could have led to acute shortage of health care professionals in these parts of the country arising from the need of the professionals to relocate safer parts of the country with the result that the available few have to work under relatively difficult conditions. Certain health care professionals such as nurses are commonly identified as being at risk for patient handling injuries, but many other health care professionals providing direct care during the course of a patient's hospital stay are also potentially at risk. Patient handling has been identified as a significant contributor to musculoskeletal injuries among health care professionals. The main purpose of this study was to assess the pattern of WMSDs, and associated ergonomic factors among health care professionals in a tertiary health institution in the North-eastern part of the country. If the pattern of WMSDs could be established and if it could be proven that a relationship exist between WMSDs and ergonomic hazards at work, then it will be necessary to adopt measures to reduce and/or eliminate the hazards completely. This study was designed to investigate the relationship between WMSDs and ergonomic hazards among health care professionals in a teaching hospital in Maiduguri, Nigeria.


  Materials and Methods Top


Design

This cross-sectional study recruited 151 health care professionals at the University of Maiduguri Teaching Hospitals in 2012.

Ethical Approval

Approval to carry out this study was obtained from the Research and Ethics Committee of the University of Maiduguri Teaching Hospital, Maiduguri. Detailed information on what the study was and what was expected of the participants was provided in participant's information sheet. Participants were required to sign the written informed consent, and they were given enough time (up to 4 months) to decide whether they will take part in this study.

Recruitment Strategies

Participants were recruited from among different Health care professionals who were duly employed at the University of Maiduguri Teaching Hospitals (UMTH) as at the time of this study, they include; Medical officers/Doctors, dentists, nurses, physiotherapists and medical laboratory scientists. Prior to this, printed recruitment posters and handbills were distributed to prospective participants in the outpatient clinics of the hospital. Recruitment posters were also displayed on notice boards at strategic areas within the hospital.

Participants

A list of all healthcare professionals from different specialties in UMTH was prepared and participants were chosen by simple random sampling based on the number of participants in each specialties. A previously compiled list of all employee in different specialities with their staff numbers was obtained and employee with the last number of the staff ID number being even number were chosen. The only criterion for eligibility to the study was at least 2 years of work experience at their current positions. Participants with histories of fractures or major trauma, degenerative disc disease, spondylitis, benign and/or malignant tumor, etc., were excluded.

Questionnaires

The questionnaire for this study was based on previous published surveys but adapted for use among Nigerians. [18] It was a self-reporting questionnaire which was adapted from the standardized Dutch Musculoskeletal (DMQ) and Nordic Musculoskeletal questionnaires (NMQ). These questionnaires have been used extensively in research studies on MSD in the general population and among different occupational groups. The NMQ is a useful tool for surveillance of work related MSD with an excellent sensitivity (82.3%-100%), specificity (51.1%-100%) and a high repeatability (Kappa = 0.63-0.90). The DMQ has been shown to have good reliability (Cronbach's alpha >0.80). Cross cultural adaptation and psychometric evaluation of the NMQ and physical work related items of the DMQ have also been done. The DMQ is a validated tool for the analysis of musculoskeletal workload and associated potential hazardous working conditions as well as musculoskeletal symptoms in worker populations. The DMQ enables a global assessment of musculoskeletal workload and other potentially hazardous working conditions by seven homogeneous indices (forces, dynamic loads, static loads, repetitive loads, climatic factors, vibration and ergonomic environmental factors) and four separate factors (sitting, standing, walking, uncomfortable postures). The questionnaire was pre-tested, simplified and adjusted to the Nigerian setting for easy understanding by Adegoke et al. [18] It was used to collect information on WMSDs and ergonomic hazards. The questionnaires consisted of three sections. The first part gather information on sociodemographic variables such as age, gender, marital status, year of experience, number of work hour per week and area of specialities. The second part consisted of questions on pattern of WMSDs while the third section focused on ergonomic hazards that may contribute to WMSDs.

Procedure

Distribution and collection of questionnaires were done by hand. According to the schedules of the selected participants, we contacted them during their work shifts in the hospital. We requested that participants complete and return the questionnaire during the same shift.

Data Analysis

Age, years of experience and number of working hours per week were expressed in mean, standard deviation and distribution of the healthcare professionals, regions of the body affected by WMSDs and self-report ergonomic hazards were expressed in percentages. The independent sample t-test was used for comparison of continuous variables such as age, years of working experience and working hours per week among those who report and those who did not report WMSDs. Chi-square were used to distinguish differences in self-report ergonomic hazards between participants with and without WMSDs among the different health care professionals. Data was stratified by MSD subcategory (neck, shoulder, elbows, upper back, wrist/hands, lower back, knees, ankles/feet and any MSD. Part of the body with MSD was used as the dependent variable, with self-report ergonomic risk factors used as the independent variables. Multiple logistic regression analysis was used to identify the relationship between parts of the body with WMSDs and self-report ergonomic risk factors. The level of significance was set at <0.05.


  Results Top


A total of 151 out of the 162 (93.2%) participants approached completed and returned the questionnaires. [Table 1] shows the participants demographic variables and WMSDs profile. Sixty of the 71 Nurses (84.5%) and 10 out of 12 (83.3%). Physiotherapists who participated in this study reported having WMSDs in one part of their body or the other. Conversely the number of physicians and dentists with WMSDs were less than those who did not experience WMSDs. Analysis with Chi-square statistical test showed significant differences between participants who reported WMSDs and those who did not among the nurses and physiotherapists (P < 0.05) which was not present among the physicians and dentists. Age, work hours per week and years of experience did not differ significantly among participants who reported WMSDs and those who did not experience WMSDs (P > 0.05).
Table 1: Participants' demographic variable and WMSDs profile


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Lower back region (71.6%) was the most common complaint area of WMSDs among participants followed by shoulder (46.8%) and neck (42.2%). Report of WMSDs was less in the hand/wrist, upper back and ankle/foot locations of the health care professionals. [Table 2] shows participants pattern of self-report ergonomic hazards at work. Working in the same position for a prolonged period i.e., sitting, standing bending over were the most common ergonomic hazards reported and each of these hazards was reported by more than 50% of the total participants with WMSDs. Other ergonomic hazards such as lifting or transferring patient, forceful exertion, reaching or working in a forward lean posture and neck flexion for more than 20° were each reported by less than 50% of the participants with WMSDs. Neck bendng (neck flexion) did not show significant difference with univariate analysis between participants with and without WMSDs (P > 0.05) which was present in other ergonomic hazards reported [Table 2]. Multiple logistic regression analysis showed statistically significant relationships (P < 0.05) among symptoms of WMSDs in all the parts of the body with all the work-related ergonomic hazards reported [Table 3].
Table 2: Patterns of participants' self-reported ergonomic hazards


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Table 3: Multivariate analysis areas of WMSDs and ergonomic hazards


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  Discussion Top


Most of the previously published works from Nigeria indicate that work-related musculoskeletal injuries among physiotherapists are very high and that it is a major health concern. This may be the first study that addresses the occupational injuries and health concerns of physiotherapists and other health care professionals from a North-eastern Nigerian perspective. The present study also investigated the relationship between the areas of WMSDs reported and work-related ergonomic risk factors.

Findings from this study revealed high occurrence of WRMSDs among healthcare practitioner particularly among the nurses (84.5%) and the physiotherapists (83.3%). This result was similar to with previous studies [16],[17],[18] In a study by Al Elisa et al., [16] it was reported that 63.9% Egyptian and 74% Saudi Physiotherapists reported more than one WRMSDs in a study involving 167 physiotherapists. A 12-month prevalence of 91.3% of WRMDs among Nigerian physiotherapists was reported by Adegoke et al. [18] 71.6% prevalence of work-related injuries was reported among Malaysian physiotherapist by Nordin et al. [15] In a similar vein, 84.4% of Nurses in Ibadan, South-western Nigeria reported having WMSDs once or more in their occupational lives with 12-months period and point prevalence rate of WMSDs was 78% and 66.1%, respectively. [19] Compared to other health care professionals, the prevalence of MSDs among physicians and dentists in this study was much lower. Similar results have been reported similar results. [17],[18],[19],[20] The high prevalence of WMSDs among physiotherapists and nurses may be related to a higher use of manual therapy techniques such as mobilizations, manipulations and massage, and lifting or transferring activities. Manual therapy has been implicated as a risk factor for WRMD, and health care professionals who routinely performed manual therapies were 3.5 times more likely to have had musculoskeletal injuries than those who did not routinely perform manual therapist. [15] This claim was supported by those of previous studies [18],[19],[20],[21] which identified lifting patients, transferring patients and performing manual techniques as the top three problematic tasks that put physiotherapists at risk for injuries. The prevalence of MSDs among physicians and dentist in this study was much lower. This may be due to comfortable working conditions and better ergonomic postures which require more sitting and less standing they adopt during most period of their routine job. Conversely, heath care professionals like physiotherapists and nurses often adopt different positions including standing, sitting forward leaning and sometimes kneeling to carry out some of their job activities. The differences in the prevalence of WMSDs among health care professionals could also be due to other factors yet to be investigated. Occupational diseases are not only physical, psychological and social disease, but could also have economic and security impacts when they reach a level of severity that directly affects working capacity. [20]

Lower back, shoulder and neck were the most common area of WMSDs reported by the participants in this study. Similar previous studies have reported lower back and neck as the most potent areas of WMSDs. [18],[20],[21] However, the inclusion of shoulder in this present study might be directly related with patient-care activities, such as lifting and transferring patients while the report of lower back and neck as areas of WMSDs might be due to prolonged standing, frequent twisting and bending in addition to lifting and transferring. [22] However, questions of the presence and/or aggravation of symptom of WMSDs in during workdays and work hours, with amelioration during weekends or holidays and when at home were not asked in the present study. This perhaps might be useful to ascertain if the reported WMSDs symptoms were either truly work related and / or non-work-related in nature. The present study also showed that WMSDs in different areas of the body was associated with ergonomic hazards. This results were similar to those of previous studies. [17],[18],[20]

The nature of stresses sustained by human back during lifting are multiple, including vertical compression, horizontal shear, rotatory torque and a variety of combination of these. During such an activity, every structural elements of the human trunk, i.e., the vertebrae, the spinal ligaments and the spinal muscles will take part and endure the stress and these different structural elements are stressed differently in different phases of any given lift. Weightlifting generates large compressive forces acting in the long axis of the spine. The magnitude of such forces depends at any given moment on the amount of weight being lifted, its acceleration and posture of the trunk. The interaction of these entities determine the strength of muscular contraction required for the accomplishment of the task. [22] In the standing posture, the centre of gravity lies in or anterior to the first lumbar vertebrae, there is virtually no muscular activity when the body is in a balanced upright position. As one stoops, the trunk approaches a horizontal position and compressive forces acting in the long axis of the spine increases. [20]

The concern about the discomfort in the neck and shoulder could be explained by the concept of load moment i.e., the concept of moment of force about a defined axis. [22] The load moment due to the weight and movement of the head during activities about a fixed axis in the neck is counteracted by neck muscular activity causing a muscular moment and consequent discomfort leading to WMSDs especially with repetitive and sustained neck movements over a long period of time. More so, movement of the head carried out at the limit of the range, can also be counteracted by passive soft tissue structures such as ligaments, joint capsules and muscular connective tissue. The induced load moments only partly reflect the joint compressive and shear forces and the load on the different neck structure. [22] When the neck is in a neutral vertical position approximately 2% of maximum muscular strength has to be used. In a slightly flexed neck position, 10% is used and in a much flexed position and in a much flexed position, 1.7-2.5% of maximum voluntary contraction maintained for an hour causes signs of fatigue in the upper trapezius muscle. [23] During lifting, transferring and this level of contraction is easily reached by arm flexion and abduction during lifting, transferring and when therapist are carrying out manual therapy even without loading the hand. Neck and shoulder muscles activity are also influenced in a complicated way by the load moments induced by the arms by the forces applied at, and weight held in the hands. Since many shoulder muscles act to stabilize the shoulder girdle joints, arm work which might seem dynamic might entail static neck and shoulder muscles activity as well. [22] Other factors considered to increase the load on neck and shoulder include working with the more elevated or advanced arms, excessive horizontal distance between the work object and a plumbline through the shoulder, a high position of the work object, high work table surface. [24] In addition, demands on precision, speed and concentration which raise the psychological stress level add further muscle activity to that induced by the load moments to cause and/or aggravate symptoms of WMSDs. [22]


  Implication for Practice Top


The incidence of neck and shoulder WMSDs complaint seems to be related to the degree of forward flexion of the neck during work [25] , it might be possible to reduce neck and shoulder muscular activity significantly during performance of certain tasks by choosing a sitting posture with the trunk slightly inclined backward. However, this backwardly inclined work posture generally requires that the work object be raised from the horizontal surface for instance by using a sloping desk or an angled attachment frame. If a backward incline position is not possible for certain work situation, a vertical posture is the second preferred option. A third option could be a posture in which normal spinal curvature is maintained but the body is inclined forward through hip flexion. [22] The possibilities of allowing micropauses described as very short but frequently reported pauses/rest period with reduced muscle activities, are of importance for muscle performance and educating employees on proper lifting techniques should be a key employee training objective. Strategies to minimize further injuries to the back range from self-protective strategies such as to avoid lifting, change of working position and decreasing the use of manual techniques whenever applicable. In addition, encouraging patient responsibility for carrying out treatment, stop working when back hurts, taking more rest breaks during the work day, change of work setting or reducing patient contact hours, exercises and further training in lifting skills.

Limitation of the Study

The survey also relied on self - reported data and participants may have either underestimated or overestimated the extent of WMSDs and ergonomic hazards they suffer.


  Conclusions Top


The occurrence of musculoskeletal complaints among nurses and physiotherapists was higher than physicians and dentists. Lower back, neck and shoulder were the three most reported WMSDs complaints areas. These musculoskeletal complaints were related with work related ergonomic hazards.

 
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