Application of the rapid upper limb assessment tool to assess the level of ergonomic risk among health care professionals: A systematic review

Abstract

BACKGROUND:

Work-related musculoskeletal disorders (WMSDs) and ergonomic risk factors are widespread problems in the healthcare sector.

OBJECTIVE:

The primary objective of this review is to evaluate the application of the Rapid Upper Limb Assessment (RULA) tool in various healthcare professionals and to assess the level of ergonomic risk among them.

METHODS:

The databases MEDLINE, EMBASE, CINAHL, LILACS, SCIELO, DOAJ, PubMed, and PEDro were searched with terms associated with ergonomics, assessment, health care providers, risk factors, workplace, and RULA. We reviewed the literature from 2000 to 2020, including studies assessing RULA’s effectiveness for evaluating the WMSD’s and ergonomic risk in health care practitioners. We excluded the studies which were not open access and freely available.

RESULTS:

Overall, 757 records were screened; of these 40 potential studies, 13 different healthcare professionals were identified as eligible for inclusion. In most studies, the RULA tool was established as an effective tool in application and evaluating the level of the ergonomic risk among them.

CONCLUSIONS:

The RULA tool assessed the high ergonomic risk levels in dental professionals and low ergonomic risk levels in professionals working in the pharmacy department, clearly suggesting potential changes in work postures were necessary to prevent or reduce these risk factors.

Keywords

Ergonomics assessment musculoskeletal disease health care providers risk factors workplace RULA

1 Introduction

Work-related musculoskeletal disorders (WMSDs) are injuries or dysfunctions that affect the muscles, nerves, tendons, joints, ligaments, and soft-tissue structures and include strains, sprains, and injuries to the surrounding structures [1]. Healthcare practitioners, particularly individuals who engage in direct patient interactions, represent the occupation-based population with the highest rate of WMSDs, due to occupational loads and awkward positions during their work-related duties [2]. Continuous movements in ergonomically adverse postures can lead to the development of MSDs, negatively affecting efficiency [3].

WMSDs place a substantial burden on society, in part due to the costs associated with work absenteeism associated with these disorders [4]. The occurrence rates and numbers of missed working days associated with WMSDs differ across varying populations, resulting in discrepancies in the financial consequences. For example, in the United Kingdom, approximately 4.5 % health care practitioners were associated with WMSDs, whereas in the Netherlands around approximately 28%, and in Germany, this number was 21% [4].

Proper assessment tools might prevent the development of musculoskeletal symptoms associated with ergonomic risks and WMSDs [5]. One important evaluation tool that has been developed is the Rapid Upper limb Assessment (RULA). The RULA is commonly used to assess the ergonomic risks in professions that are frequently associated with WMSDs in the upper extremities [6] as it demonstrated higher intra-rater reliability than inter-rater reliability. Corlett and McAtamney developed the RULA (1993) as an observational tool, used to evaluate an individual’s vulnerability to load aspects due to the posture of the head, neck, arms, trunk, upper limb, and the support of the lower limbs, in addition to muscle use and additional loads during work. The scoring system considers all of these factors to produce a total RULA score, ranging from one to seven. This score evaluates the possibility of injury as a result of musculoskeletal burden. Higher scores indicate a greater likelihood of musculoskeletal damage. Scores of one or two indicate that the scored work posture is satisfactory, as long as it is not maintained or performed repetitively for extensive periods of time. Scores of three or four indicate that additional examination is necessary and that postural changes may be necessary. Scores of five or six suggest that postural changes should be implemented rapidly, and a score of seven suggests that immediate postural changes are required [7].

The primary objective of the present study was to perform a systematic review that focused on the application of the RULA tool among healthcare practitioners and to assess the level of ergonomic risk among them.

2 Methodology

The protocol is registered at INPLASY under no. 202110120.

2.1 Search Strategy for data extraction

An efficient review of methodology was utilized to focus this present research question by using methods to minimize the bias in collecting, reviewing, and describing the research evidence, following the procedures outlined by PRISMA. The search databases included for this review were MEDLINE, EMBASE, CINAHL, LILACS, SCIELO, DOAJ, PubMed, PEDro, Saudi digital library, NHS EED, PROSPERO, Google Scholar, Scopus, and Web of Science. We searched these databases from 2000 until 2020, and 757 studies were obtained in the initial search. The following search terms were used: ergonomics; assessment; health care providers; musculoskeletal disease; workplace, risk factors, and RULA. The resultant levels of methodological quality of included cross-sectional and observational studies were evaluated using Quality assessment tool for observational, Cohort, and Cross-sectional studies provided by study quality assessment tools of National Institute of Health (NIH) scale, USA; included case-control studies were evaluated by Quality assessment of case-control studies provided by study quality assessment tools of NIH scale, USA; included experimental studies were evaluated by Quality assessment tool for Before-After (pre-post) studies with no control group provided by study quality assessment tools of NIH scale, USA; and included randomized control trials (RCTs) were evaluated by using Physiotherapy Evidence Database (PEDro scale). All the studies, which all scored six or more points on these scales, were included for the review process, and finally, 40 studies were included in this systematic review.

2.2 Screening methods

Two independent reviewers screened the relevant studies based on the inclusion criteria and extracted the risk of bias. The reviewers extracted the full texts of all relevant cross-sectional, experimental, observational, case-control, and randomized control trials.

2.3 Categories of studies

In this systematic review, we only included the studies that determined the application of RULA among various health care professionals.

2.4 Selection criteria

2.4.1 Inclusion and exclusion criteria

Inclusion criteria: Articles published in English with full text, published from the year 2000 until 2020; Studies that evaluated the application of RULA and assessed the level of ergonomic risks in different health care professionals.

Exclusion criteria: Identical publications; Studies related to commentaries, professional opinions, and letters to the editor; Study articles with inaccessible full text, identical, and who did not assess musculoskeletal outcomes were also excluded.

2.5 Quality assessment / risk of bias analysis

The evaluation of the risk of bias of the incorporated studies was approved out with PRISMA guidelines [8]. The risks of bias are evaluated in relationship to the particular design, conduct, and outcomes. Two reviewers resolved all differences through discussion, and a third reviewer was involved when no consensus was reached.

2.6 Types of outcomes

The primary outcome measure for the present systematic review was to evaluate the WMSDs among health care professionals by using RULA. The secondary outcome was to assess the level of ergonomic risks among them.

2.7 Methodological quality

Two independent reviewers assessed the included studies, and the differences were rectified together with a third reviewer until an agreement was reached. These assessors were not blinded towards the authors, organizations, or journals during the review procedure. The quality of cross-sectional and observational studies were selected based on the NIH scale (14-points) scoring system as good (9–10 points), fair (6–8 points), and poor (< 6 points). However, the quality of experimental and case-control studies was selected based on NIH scale (12-points) scoring system as good to fair (> 6 points) and poor (< 6 points). Both the reviewers evaluated the studies cautiously, and the adjustments were resolved together with a third reviewer until an arrangement was reached. Lastly, the quality of the randomized control trials was carefully chosen based on the PEDro scoring classification as excellent (9–10 points), good (6–8 points), fair (4–5 points), or poor (< 4 points). In case of disagreement between two reviewers, the decision of the third reviewer was considered to be final.

3 Results

In total, 757 studies were noticed using the search strategy which has been mentioned above. Out of which, 501 studies were excluded for not assessing the musculoskeletal outcomes. After a careful screening of the remaining 256 studies based on the inclusion standards, 169 studies lack adequate data; 21 studies did not have full text; 18 studies did not address the research question; 8 studies provided irrelevant results were excluded, and the remaining 40 studies were selected for this review. We followed PRISMA guidelines for reporting this review results flow diagram (Fig. 1).

Fig. 1

PRISMA flow diagram explaining the results of the search.

In total, 13 healthcare specialty categories were identified, including surgeons [9 –22], dental practitioners [23 –34], nurses [35 –37], pharmacists [38, 39], ophthalmologists [40], otology physicians [41], microbiologists [42], laboratory technicians [43], medical sonographers [44], laryngologists [45], mammographers [46], biomedical scientists [47], and clinical workers [48]. The numbers of studies identified for each healthcare specialty are presented in Table 1.

Table 1

No. of studies according to health care specialty wise

Health care specialty	No. of studies
Surgeons	14
Dental practitioners and students	12
Nurses	3
Pharmacists	2
Ophthalmologists	1
Otology Physicians	1
Microbiologists	1
Laboratory technicians	1
Medical sonographers	1
Laryngologists	1
Mammographers	1
Biomedical Scientists	1
Clinical workers	1
Total Studies	40

The NIH scale scores of included cross-sectional are listed in Table 2a; observational studies are listed in Table 2b, case-control studies in Table 3, experimental studies in Table 4, and PEDro scores for RCTs are listed in Table 5.

Table 2a

(Cross-sectional Studies) Quality assessment tool for Observational, Cohort, and Cross-sectional studies provided by study quality assessment tools used by NIH scale

S. No	Author/ Reference	1	2	3	4	5	6	7	8	9	10	11	12	13	14	NIH score
1	McLaren et al. [24]	Y	Y	Y	Y	N	N	Y	N	NA	NA	Y	Y	N	N	7/12
2	Movahhed et al. [26]	Y	Y	Y	Y	N	N	Y	N	Y	NA	Y	NR	N	N	7/12
3	Sezgin et al. [37]	Y	Y	Y	N	Y	N	Y	N	N	NA	Y	Y	N	N	7/13
4	Tirgar et al. [28]	Y	Y	N	N	N	N	Y	Y	Y	NA	Y	NR	N	N	6/12
5	Rafie et al. [29]	Y	Y	Y	Y	NR	N	Y	N	Y	NA	Y	N	N	Y	8/12

Table 2b

(Observational studies) Quality assessment tool for Observational, Cohort, and Cross-sectional studies provided by study quality assessment tools used by NIH scale

S. No	Author/ Reference	1	2	3	4	5	6	7	8	9	10	11	12	13	14	NIH score
1	Mills et al. [23]	Y	Y	NR	NR	Y	Y	Y	N	Y	Y	Y	N	N	Y	9/12
2	Van ’t Hullenaar et al. [9]	Y	Y	N	Y	NR	N	Y	NA	Y	Y	Y	N	N	N	7/12
3	Yazdanirad et al. [38]	Y	Y	NR	N	N	N	Y	Y	Y	N	Y	N	NA	Y	7/12
4	Govil et al. [13]	Y	Y	NR	N	N	N	Y	Y	Y	N	Y	NR	N	N	6/12
5	Van ’t Hullenaar et al. [10]	Y	Y	NR	N	N	NR	Y	Y	Y	N	Y	N	N	N	6/12
6	Li et al. [11]	Y	Y	N	NA	N	Y	Y	Y	Y	N	Y	N	N	Y	8/13
7	Dabholkar et al. [12]	Y	Y	NR	N	N	N	Y	Y	Y	Y	Y	NR	N	Y	7/12
8	Marcon et al. [25]	Y	Y	N	NR	N	N	Y	Y	Y	N	Y	N	NR	N	6/12
9	Carvalho et al. [42]	Y	Y	N	N	N	N	Y	Y	Y	NR	Y	NR	NR	N	6/11
10	Rosso et al. [39]	Y	Y	N	N	N	Y	Y	Y	Y	N	Y	N	N	NR	7/13
11	Park et al. [27]	Y	Y	NR	N	N	Y	Y	N	Y	N	Y	NR	N	N	6/12
12	Corrocher et al. [30]	Y	Y	N	NR	N	N	Y	Y	Y	N	Y	N	NR	N	6/12
13	Govil et al. [41]	Y	Y	NR	N	N	N	Y	Y	Y	N	Y	NR	N	N	6/12
14	Maulik et al. [43]	Y	Y	NR	NR	N	N	Y	Y	Y	Y	Y	N	N	N	7/12
15	Golchha et al. [31]	Y	Y	NR	NR	N	N	Y	Y	Y	N	Y	N	N	Y	7/12
16	Roll et al. [44]	Y	Y	N	NR	NA	Y	Y	Y	Y	N	Y	N	N	Y	8/12
17	Garcia et al. [32]	Y	Y	NR	N	N	Y	Y	Y	Y	N	Y	N	N	Y	8/13
18	Craven et al. [17]	Y	Y	N	N	N	Y	Y	Y	Y	N	Y	N	N	N	7/14
19	Noh et al. [33]	Y	Y	NR	N	N	N	Y	Y	Y	N	Y	N	NR	N	6/12
20	Hermanson et al. [22]	Y	Y	N	N	N	N	Y	Y	Y	N	Y	N	NR	N	6/13
21	Youssef et al. [18]	Y	Y	N	NR	N	N	Y	Y	Y	N	Y	N	N	Y	7/13
22	Sanchez-Margallo et al. [19]	Y	Y	N	NR	N	N	Y	Y	Y	Y	Y	N	NR	Y	8/12
23	Taylor-Phillips et al. [46]	Y	Y	NR	N	N	N	Y	Y	Y	N	Y	N	N	Y	7/12
24	Lee et al. [20]	Y	Y	N	N	N	N	Y	Y	Y	N	Y	N	NR	N	6/12
25	Person et al. [21]	Y	Y	N	N	N	Y	Y	N	Y	N	Y	N	N	N	6/12

^*Y = Yes (Score = 1), N = No (Score = 0), NA = Not applicable (Score nullified), NR = Not reported (Score = 0), CD = cannot determine (score = 0). 1. Research Question. 2. Study population. 3. Participation Rate. 4. Uniform eligibility criteria. 5. Sample size justification. 6. Exposure assessed prior to outcome. 7. Sufficient timeframe to see an effect. 8. Different levels of exposure examined. 9. Exposure measures valid, reliable, and consistent. 10. Repeated exposure measurement. 11. Outcome Measures valid, reliable, and consistent. 12. Blinding of outcome assessors. 13. Follow up rate. 14. Statistical Analysis.

Table 4

Quality assessment of randomized controlled trials using Physiotherapy Evidence Database (PEDro) scale

S. No.	Author/References	1	2	3	4	5	6	7	8	9	10	11	PEDro score (11)
1	Singh et al. [14]	Y	Y	N	Y	Y	Y	N	Y	N	Y	N	7/11
2	Bensignor et al. [15]	Y	Y	Y	Y	N	N	Y	Y	N	Y	Y	8/11

^*Y = Yes (Score = 1), N = No (Score = 0). 1. Eligibility criteria were specified. 2. Subjects were randomly allocated to groups. 3. Allocation was concealed. 4. The groups were similar at baseline regarding the most important prognostic indicators. 5. There was blinding of all subjects. 6. There was blinding of all therapists who administered the therapy. 7. There was blinding of all assessors who measured at least one key outcome. 8. Measures of at least one key outcome were obtained from more than 85% of the subjects initially allocated to groups. 9. All subjects for whom outcome measures were available received the treatment or control condition as allocated or, where this was not the case, data for at least one key outcome was analyzed by “intention to treat”. 10. The results of between-group statistical comparisons are reported for at least one key outcome. 11. The study provides both point measures and measures of variability for at least one key outcome.

Among the five cross-sectional studies, four studies were done on dental practitioners [24 , 29], and one study was performed on intensive care unit nurses [37]. These included cross-sectional studies have NIH scale scores that range between 6 and 8 points (Table 2a). However, the majority of the studies in this review were observational studies. Among 25 studies, 11 studies were done on different surgeons [9–13 , 17–22], 7 studies were done on dental practitioners [23 , 30–32], 2 studies on professionals working in the pharmacy department [38, 39], and one each study on otology physicians [13], micro-biology staff [42], medical laboratory technicians [43] medical sonographers [44], and mammographers [46]. These included observational studies have NIH scale scores that range between 6 and 9 points (Table 2b).

Table 3

Quality assessment of Case-control studies provided by study quality assessment tools of NIH scale

S. No.	Author/ Reference	1	2	3	4	5	6	7	8	9	10	11	12	NIH score
1	Statham et al. [45]	Y	Y	N	Y	Y	NR	N	NR	N	Y	Y	N	6/12
2	Bartnicka et al. [16]	Y	Y	Y	Y	Y	N	N	NR	N	Y	Y	Y	8/12

^*Y = Yes (Score = 1), N = No (Score = 0), NR = Not reported (Score = 0), CD = cannot determine (score = 0). 1. Research Question. 2. Study population. 3. Sample size justification. 4. Uniform controls. 5. Uniform eligibility criteria. 6. Case and Control definitions. 7. Random Allocation. 8. Concurrent Controls. 9. Exposure assessed prior to outcome. 10. Exposure measures and assessment. 11. Blinding of outcome assessors. 12. Statistical analysis.

Along with this, two case-control studies [16, 45] (Table 3) and two RCTs [14, 15] (Table 4) were included in this review. All these four studies have been done on surgeons. The case-control studies have NIH scale scores that range between 6 and 8 points and included RCTs have PEDro scale scores that range between 7 and 8 points.

Table 5

(Experimental studies) Quality assessment tool for Before-After (pre-post) studies with no control group provided by study quality assessment tools of NIH scale

S. No.	Author/References	1	2	3	4	5	6	7	8	9	10	11	12	NIH score (11)
1	Ratzlaff et al. [40]	Y	Y	Y	Y	N	Y	Y	Y	N	N	Y	N	8/12
2	Garosi et al. [35]	Y	Y	Y	N	N	N	Y	Y	N	Y	Y	N	7/12
3	Sezgin et al. [36]	Y	Y	N	N	Y	Y	Y	N	Y	N	Y	N	7/12
4	Shafti et al. [48]	Y	Y	Y	Y	Y	N	Y	N	N	N	Y	N	7/12
5	Gandavadi et al. [34]	Y	Y	Y	Y	Y	N	N	Y	N	Y	Y	N	8/12
6	Kilroy et al. [47]	Y	Y	Y	Y	N	Y	Y	N	N	Y	Y	N	8/12

^*Y = Yes (Score = 1), N = No (Score = 0). 1. Was the study question or objective clearly stated? 2. Were eligibility/selection criteria for the study population pre-specified and clearly described? 3. Were the participants in the study representative of those who would be eligible for the test/service/intervention in the general or clinical population of interest? 4. Were all eligible participants that met the pre-specified entry criteria enrolled? 5. Was the sample size sufficiently large to provide confidence in the findings? 6. Was the test/service/intervention clearly described and delivered consistently across the study population? 7. Were the outcome measures pre-specified, clearly defined, valid, reliable, and assessed consistently across all study participants? 8. Were the people assessing the outcomes blinded to the participants’ exposures/interventions? 9. Was the loss to follow-up after baseline 20% or less? Were those lost to follow-up accounted for in the analysis? 10. Did the statistical methods examine changes in outcome measures from before to after the intervention? Were statistical tests done that provided p values for the pre-to-post changes? 11. Were outcome measures of interest taken multiple times before the intervention and multiple times after the intervention (i.e., did they use an interrupted time-series design)? 12. If the intervention was conducted at a group level (e.g., a whole hospital, a community, etc.) did the statistical analysis take into account the use of individual-level data to determine effects at the group level?

Concerning the six experimental studies, two studies were done on nurses [35, 36], and one each study on ophthalmology residents [40], clinical workers [48], dental professionals [34], and biomedical scientists [47]. These included experimental studies have NIH scale scores between 7 and 8 points (Table 5).

The associated information for the included studies according to the study type, population, outcome measures, and RULA score related to various health care professionals are reviewed in Table 6.

Table 6

Summary of the study design, population, outcome measures used, and RULA score related to health care practitioners

Citation	Study design	Population	Year, Country	Outcome measures used	RULA Score	Conclusion
Mary E. Mills et al.	Observational Study	Dental students and dental hygiene students.	2020, USA	Photograph method, and RULA	3	Overall, it was established that the use of photographs for risk assessment through the RULA tool was effective in decreasing the students risk scores for MSDs (23).
Ratzlaff T.D. et al.	Prospective interventional pilot study.	Ten ophthalmology residents	2019, Canada	RULA	> 4	The RULA injury risk scores reduced after completion of the module (95% CI 2.10¡2.77), representing a slighter risk for injury to the Ophthalmologist (40).
Van’t Hullenaar et al.	Observational study	First assistants during robotic assisted surgery.	2019, Netherlands	RULA, Dutch Musculoskeletal Questionnaire	4– 5	RULA scores shown high-risk ergonomic risk scores for all measured movements that were accomplished during surgery (9).
Garosi, E et al.	Experimental Study	Nurses	2019, UAE	Borg scale CR10, EMG, RULA	3	The postures of the wrist, arm, and shoulder regions were adjusted from Rapid Upper Limb Assessment action level 3 to 2 (35).
Yazdanirad et al.	Comparative Study	Pharmaceutical, automotive, and assembly in the Isfahan province.	2018, Turkey	RULA, LUBA, NERPA, NMQ.	2– 4	Low-risk levels in NERPA, medium-risk levels in LUBA, and high-risk levels in RULA are assessed (38).
Goyil, N et al.	Observational study	Two Neuro-Otology physicians	2018, USA	RULA	2– 4.5	Overall, the RULA scores were 4.5 with patients in the seated position, and 2 with patients in the supine lying position (41).
Sezgin, D et al.	Pre and post-test design	ICU Nurses	2018, Turkey	Descriptive of Nurses and Ergonomic Risk Reporting Form, RULA, ICU Environment Assessment Form, and Personal interviews form	4– 5	RULA ergonomic risk scores were considerably reduced, while exercise frequency was improved (36).
McLaren et al.	Cross-sectional study	Dental students	2018, United Kingdom	RULA	5– 6	No students were categorized as having satisfactory posture and most required postural variations soon (24).
Van’t Hullenaar et al.	Comparative study	Surgical interns and residents using the da Vinci skills simulator during robotic surgery.	2018, Netherlands	RULA, Mental and physical load scores, NASA-TLX, and LED score were registered.	3– 4	The intervention group showed less irrelevant movement and a slighter deviation from the neutral position of the hands. The intervention group also scored considerably better on the RULA tool than the other group (10).
Li, Z.L et al.	Preliminary study	Plastic surgeons	2017, China	MOO, and RULA.	> 3	The results exhibited that it is likely to expect the RULA scores for the series of postures and quantify risk assessment, mainly in the collection and fitting of loupes and the description of working height for surgeons (11).
Dabholkar et al.	Observational study	Laparoscopic surgeons	2017, India	RULA	4– 5	Physical, ergonomic risk is medium as projected by the RULA scoring method, through this minimally invasive surgical procedure, demanding the application of modification in the ergonomic practices (12).
Marcon et al.	Observational study	Operative dentists	2017, Italy	RULA, and NERPA	3– 6	Risk of MSD’s were evaluated in an objective and precise way (25).
Govil N et al.	Observational design	Otology surgeons	2017, USA	RULA	3– 5	The risk of musculoskeletal disorders surges as the RULA score increases (13).
Singh, R et al.	Cross over randomized study	Vaginal surgery doctors	2016, USA	CMDQ, SURG-TLX, and RULA.	5– 6	RULA postural scores revealed moderate to high musculoskeletal risk in the neck and shoulders across surgeons, and the chairs did not have an outcome on the postural scores (14).
Bensignor et al.	Randomized crossover stratified study	Laparoscopic surgeons	2016, France	RULA	> 6	The mean of the three tasks’ RULA score was suggestively lower with Jaimy chair, and the postural ergonomics were developed (15).
Shafti A et al.	Experiment study	Clinical workers	2016, France	EMG, RULA, Borg Scale	4– 5	RULA score and EMG measurements specified the best presentation in identifying the task difficulty and discomfort (48).
Movahhed T et al.	Cross sectional study	Dental students	2016, Iran	RULA	5– 6	There was no significant association between RULA score with working posture (26).
Carvalho F et al.	Observational study	Microbiology staff	2016, Portugal	RULA	> 6	Results of the Rapid Upper Limb Assessment results revealed that the risk for the development of MSD is present in all tasks (42).
Rosso C.B. et al.	Observational study	Pharmacists	2016, Brazil	RULA, Deparis, and ABC analysis	> 6	The findings permitted suggestions for improvement, related primarily to the procedure of drug dispensation, organization, and preparation of the work environment (39).
Park H.S. et al.	Observational study	Dentists	2015, Korea	RULA, and QEC	> 6	The RULA examination of the dentists’ work posture specified, “immediate improvement required” in the posture (27).
Sezgin D et al.	Cross sectional study	Intensive care unit Nurses	2015, Turkey	RULA	> 6	The Rapid Upper Limb Assessment score for the patient turning movement was higher than for the twisting down motion (37).
Tirgar A et al.	Analytic cross-sectional study	Dental practitioners	2015, Iran	RULA, Demographic questionnaire, NMQ, BDA, and CCFT.	> 6	Based on the RULA scores, 93.3% of the subjects had a despicable position during uplifting practices (28).
Bartnicka J.et al.	Case Study	Surgical ward health practitioners	2015, Poland	OWAS, REBA, RULA, and NIOSH.	3– 6	The principle of this method to knowledge-based ergonomic assessment is the likelihood to re-use the same evidence depending on the purpose and the process of ergonomic analysis (16).
Rafie F et al.	Cross-sectional Study	Dentists	2015, Iran	NMQ, and RULA.	> 6	The current findings exhibited that the unsuitable posture of dentists during work has a substantial effect on WRMD’s (29).
Corrocher et al.	Observational study	Undergraduate dental students	2014, Brazil	RULA	> 5	The compromise of developing musculoskeletal disorders was high in dentistry students; this hazard was not associated with gender, type of dental procedure, and region being treated (30).
Maulik S et al.	Questionnaire technique	Laboratory technicians	2014, India	NMQ, VAS, and RULA.	> 6	The final RULA score of 6±1.02 highlights poor workstation design, which resulted in an unnatural posture (43).
Golchha V et al.	Survey method	Dental practitioners	2014, India	RULA, and NMQ	1– 2	RULA can be utilized as a screening tool for postural risks following a short training session irrespective of the evaluator’s knowledge in postural risk assessments (31).
Roll S.C et al.	Pilot observational study	Medical sonographers	2014, USA	RULA	3– 5	Overall, RULA scores ranged from 3.11 to 5.00, with upper extremity averaging the highest risk associated with increased musculoskeletal discomfort (44).
Garcia P.P et al.	Observational study	Dental students	2013, Brazil	OWAS, and RULA	> 6	The risk of musculoskeletal disorders in dental students projected by the OWAS method was medium, whereas the same risk by the RULA method was exceptionally high (32).
Craven R et al.	Observational study	Gynaecology oncology surgeons	2013, USA	RULA, and SI method	> 6	Ergonomic assessment of surgeon activity leads to a mean RULA score of 6.46 (maximum possible RULA score, 7), representing a need for additional investigation (17).
Noh H et al.	Observational study	Dental hygienists	2013, Korea	RULA, and REBA	> 6	RULA score found that the shoulders and wrists were almost overloaded (33).
Hermanson J.E. et al.	Observational and Analytical study	Physicians performing surgery	2012, USA	Body Map Assessment, RULA	> 6	The findings have revealed that the most significant concerns were the discomforts in the neck, shoulders, arms/wrists, and back (22).
Youssef Y et al.	Observational study	Laparoscopy surgeons	2011, USA	RULA, NASA-TLX, and VRS	1– 4	RULA scores were always less for the standing technique and higher for the side-standing procedure, irrespective of whether one- or two-handed (18).
Statham M.M. et al.	Prospective case-control study.	Laryngologists	2010, USA	RULA	> 6	RULA and biomechanical analyses have recognized lower-risk surgeon positioning to be applied during micro-laryngeal surgery (45).
Sanchez-Margallo, F.M. et al.	Data collection study	Laparoscopic surgeons	2009, United Kingdom	RULA	> 6	RULA analyses that these positions mean a high risk to suffer from muscle alterations (19).
Taylor-Phillips S. et al.	Observational Study	Mammographers	2008, USA	RULA	5– 6	RULA postural analysis showed no overall increase in MSD risk level (46).
Gandavadi A et al.	Experimental design	Dental students	2007, United Kingdom	RULA, and Photograph method	> 6	RULA has identified that dental students using a Bambach saddle seat could sustain an acceptable working posture during dental treatment, and this seating may decrease the development of WRMD’s (34).
Lee E.C. et al.	Comparative Study	Minimal invasive technique surgeons	2005, USA	JSI, and RULA	4– 7	The JSI and RULA scores for all four tasks were considerably lower for the telerobotic technique than the manual one (20).
Person, J.G. et al.	Observational Study	Laparoscopy surgeons	2001, Canada	RULA	> 6	Ergonomic stress scores were reasonably high throughout the procedure, predominantly for the wrist (21).
Kilroy, N. et al.	Clinical Trail	Biomedical Scientists	2000, Ireland	NMQ, BDC, and RULA.	3	The majority had a RULA grand score of three. Examination of findings specifies that RULA scores generally resemble reporting symptoms of NMQ and BDC (47).

Note: The abbreviations of terms used in the table were provided below. Borg Scale CR10: Borg Scale Category ratio 10. CCFT: Craniocervical Flexion test. LUBA: loading on the upper body assessment. NIOSH: National Institute for Occupational Safety and Health. NERPA: new ergonomic posture assessment. OWAS: Ovako Working Posture Assessment System. NMQ: Nordic Standardized Musculoskeletal Questionnaire. VAS: Visual Analogue Scale. NASA-TLX: NASA Task Load Index. SI: Strain index. SURG-TLX: Surgery Task Load Index. VRS: Virtual reality Simulator. MOO: Multi-objective optimization. JSI: Job Strain index. CMDQ: Cornell Musculoskeletal Discomfort Questionnaires. REBA: Rapid Entire Body Assessment. QEC: Quick Exposure Check. BDA: Body Discomfort Assessment questionnaire.

4 Discussion

This systematic review is the first of its kind, in which we examined the effectiveness of application of RULA to assess the level of ergonomic risk among various healthcare practitioners. The incidence rates and outcomes broadly differed between the studies, possibly due to evaluating of different factors, including physical factors, anthropometric determinants, psychosocial job requirements, public interactions at exertion, and interpersonal social factors, which were correlated with WMSDs. We observed the highest level of ergonomic risk (RULA score > 6), especially in surgeons and dental professionals, and less ergonomic risk level (RULA score 2–3) in otology professionals. All of these studies were implemented in actual workplaces, which included both in-patient and outpatient departments.

4.1 Plastic surgery

Li et al. [11] assessed the factors that contributed to pain and discomfort in the neck among plastic surgeons when wearing head-mounted magnifiers during operations. The results showed that different RULA scores (beyond 3) were obtained for a variety of positions and suggested that RULA can be useful for performing risk assessments and reducing occupational risks, particularly when selecting magnifiers and modifying the height of the operating table for surgeons.

4.2 Neurotology

Govil et al. [13] evaluated the ergonomically optimal position of a patient (sitting versus supine) during otologic procedures by using RULA. The RULA scores recorded for neurotologists were significantly lower when the patient was in the supine position compared with the seated position. This study suggested that patient position may contribute to the work-related stress placed on an otolaryngologist’s upper extremities during otology procedures.

4.3 Robotic-assisted surgery

Van’t Hullenaar et al. [9] assessed the ergonomic risks associated with the performance of robot-assisted surgery using three techniques: RULA, Nordic musculoskeletal questionnaire (NMQ), and photographic technique. RULA scores revealed high ergonomic risks for all evaluated activities in which the tissue drawing techniques were identified as the activities with the maximum physical workload [9]. In another study [10] by the same authors, an intervention group who received proper training during robot-assisted surgery demonstrated better ergonomic postures than the control group, based on superior RULA scores. In an additional study performed by Lee et al. [20], thirteen contestants with no familiarity as chief surgeons in endoscopic surgery executed a set of replicated surgical tasks by means of telerobotic system and a manual endoscopic surgery system. Telerobot use during endoscopic surgery was associated with an improvement in ergonomics, as assessed by lower RULA scores. The surgeons in this study also reported that this technique was less stressful than the manual technique.

4.4 Laparoscopy

A few researchers focused on laparoscopic surgeons and revealed that these healthcare practitioners were at ergonomic risk according to the RULA method [12 , 21].

4.5 Vaginal surgery

One randomized cross-over study performed by Singh et al. [14] assessed the effects of four different chairs used by gynecologists during vaginal surgery; a conventional curved chair, a round chair with a backrest, a saddle chair with a backrest, and a Capisco chair. They revealed that the RULA scores showed moderate to high ergonomic risks for the neck and shoulder regions across surgeons. They also concluded that the chair discomfort scores for the conventional curved chair and the saddle chair were considerably higher than the remaining two chair types during surgery.

4.6 Other studies in surgery

Bartnicka et al. [16] analyzed various ergonomic methods to assess the working conditions of the nursing team and surgeons in surgical departments and revealed that they required significant bodily and postural efforts due to the difficult positions at work. The RULA method and other evaluation methods were found to be effective for assessing the postural stress endured by these practitioners. Finally, Hermanson et al. [22] also concluded that the estimated frequency of WMSDs among at-risk physicians appeared to be high.

4.7 Dental department

This section is further divided into dental practitioners and dental students

4.8 Dental practitioners

Marcon et al. [25] evaluated three unique set-ups in which dental practitioners performed operations with bare eyes, with medical lenses, or using a surgical microscope and compared the postural consequences of these three different patterns. The RULA risk evaluation score [5, 6] was higher in the neck and spinal regions when using the medical lenses and bare eyes compared with the use of a surgical microscope. This RULA score was similar to those determined by Park et al. [27] and Trigar et al. [28]. Park et al. indicated that the posture required to handle maxillary second molars was more intolerable than that required to treat the anterior teeth, and Trigar et al. added that female dental specialists were at higher ergonomic risk than male practitioners.

4.9 Dental students

Some authors assessed the ergonomic risks in dental students while working in dental clinics. Mills et al. [23] suggested that the RULA method made the participants more aware of their posture and enhanced the self-consciousness of ergonomics, which decreased the hazards of developing WMSDs among dental hygiene students. Other studies [24, 26] reported that most dental undergraduates did not have acceptable working postures and were at a high risk of developing WMSDs. Movahhed et al. also showed no substantial relationship between RULA scores and gender, educational year, or dental clinic division.

4.10 Nursing

Garosi et al. [35] designed an infusion connector instrument and compared it against the use of a manual connection while performing nursing tasks. The RULA risk score was reduced from 3 to 2 when the designed tool was utilized. Sezgin et al. [36] assessed the ergonomic risk factors in nurses in an intensive care unit. The mean RULA scores significantly decreased when the exercise frequency among nurses increased, resulting in reduced musculoskeletal pain and ergonomic risk among nurses. Another study, performed by Sezgin et al., [37] investigated the incidence of musculoskeletal symptoms among intensive care nurses. Most musculoskeletal symptoms were reported in the legs and back, especially when the nurses rotating or twisting down the patient.

4.11 Pharmacy

Yazdanirad et al. [38] compared three different ergonomic risk assessment methods; RULA, loading on the upper body assessment (LUBA), and new ergonomic posture assessment (NERPA) for the evaluation of the upper extremity MSD’s in workers in the pharmacy department. The results demonstrated that the RULA was the best technique for evaluating MSD’s between the three tested methods. Rosso et al. [39] performed an ergonomic assessment of employees in an emergency pharmacy department, using Deparis, RULA, and ABC analysis methods. All three methods were found to improve comfort and working conditions for the pharmacy workers.

4.12 Ophthalmology

Ratzlaff et al. [40] categorized variations in body position in ten ophthalmology residents during the performance of a uniform slit-lamp examination. All practitioners received an educational training program on ergonomics, and the ergonomic risk was assessed pre-and post-training using RULA, which was analyzed using biomechanical software. The outcome of their study showed that training offered the promising ability to decrease injury risk.

4.13 Microbiology

Carvalho et al. [42] evaluated microbiologists under real working conditions and assessed associated WMSD’s. RULA was used to evaluate the level of risk, and the RULA scores showed that a risk for the progression of MSD’s was identified for all tasks. They suggested the implementation of precautionary measures to decrease the level of risk.

4.14 Laboratory

Maulik et al. [43] concluded that technological developments in medical laboratories might have increased the number of ergonomic risks for laboratory professionals due to their nature of work. The RULA scores emphasized that poor workstation strategies resulted in abnormal work postures. The use of administrative and addition of engineering pedals may be able to considerably reduce these ergonomic hazards and further decrease the final RULA score.

4.15 Medical Sonography

The working postures of medical sonographers were assessed because 90% of these professionals often suffer from musculoskeletal pain and discomfort. Roll et al. [44] conducted a pilot study to identify the relationship between sonographer pain and work environments during 24 sonographic examinations using RULA. Overall, the RULA scores revealed poor upper extremity postures, which were associated with musculoskeletal pain and discomfort.

4.16 Micro laryngoscopy

In a case-control study, Statham et al. [45] examined three different micro laryngeal operational positions in laryngologists; a sustained work position in a chair with arm support, a sustained position with the arms relaxing on a mayo stand, and a position with the arms unsupported. RULA and biomechanical evaluations indicated a lower risk associated with laryngoscopy surgeon positioning in a chair with arm support, which must be used during micro laryngeal surgery.

4.17 Mammography

In the United Kingdom, the Breast Screening program, has increasingly been shifting from film to digital mammography, which has been associated with a concomitant modification in workstation ergonomics. Three workstation types were examined: one with film and digital mammograms, one with only film mammograms, and one with only digital mammograms. RULA scores showed no increase in the WMSD hazard levels associated with the shift from a film only to a digital mammogram workstation [46].

4.18 Other studies

An ergonomic evaluation of female microbiologists was performed by Kilroy et al. [47] using RULA, NMQ, and the body discomfort chart (BDM). This study was piloted in three stages: before, during, and after the intervention. The final RULA scores revealed a decrease in the incidence of musculoskeletal problems and body distress after the intervention. As a final study, Shafti et al. [48] determined the importance of using RULA to evaluate ergonomics in clinical work environments.

Even though RULA was found to be an efficient tool in assessing the level of ergonomic risk among health care professionals, some of the researchers found some unsatisfactory results. Van’t Hullenaar et al. stated that the tissue drawing technique was the most demanding activity performed by nurses throughout the robot-assisted surgery, but RULA delivered a highly unfavorable score during this technique [9]. Van ’t Hullenaar et al. concluded that the low RULA scores reported in the control group, which indicated ideal posture, were not guaranteed when utilizing the console of the da Vinci surgical system during training [10]. Dabholkar et al. determined that the postural hazard was medium, based on the RULA scoring method during the withdrawal period of this minimally invasive surgical technique, requiring modifications to ergonomic practices [12]. Govil et al. were not able to identify differences in RULA scores between male and female surgeons, likely due to the small sample size of the research [13]. Bartnicka et al. used OWAS, RULA, REBA, and NOISH approaches to perform an ergonomic risk assessment in surgical divisions and specified that in Polish conditions, the OWAS method was more useful than the other tested ergonomic methods [16]. Youseff et al. reported that surgeons who perform laparoscopic procedures experienced greater wrist flexion and bending, despite receiving low RULA scores, suggesting conflicting results that could be due to the compensatory upper limb and trunk movements. [18]

Golchha et al. concluded that the posture evaluated by RULA was not correlated with WMSD documented using the Standard Nordic Musculoskeletal Questionnaire among the dental practitioners in their study [31]. Garcia et al. showed that the RULA assessment method requires more time and preparation for the evaluators to apply because the risk scores are primarily evaluated based on measurements of the abnormalities in the body evaluated segments [32].

The present study has some limitations. First, due to the lack of language expert’s availability, we limited our search to papers published in English language. Second, due to digitalization, the grey literature and manual search were limited in this review, so the likelihood happens that some studies were ignored.

Further research should include different interventional strategies, especially in high-risk health care professionals, to evaluate the ergonomic risk based on RULA scores.

5 Conclusion

The current systematic review examined the significance of RULA for assessing the level of ergonomic risk among healthcare practitioners. In some studies, RULA was used in addition to other assessment tools, however RULA was found to provide more reliable results than these other approaches. Overall, this review suggested that RULA is an effective method for evaluating the postural risks associated with different health sectors as it provides a user-friendly evaluation tool that needs minimal time, effort, and equipment.

Funding

The authors are thankful to the Deanship of Scientific Research, King Khalid University, Abha, Saudi Arabia for financially supporting this work (RGP 2/40/42).

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical standard

This article does not contain any studies with human or animal subjects performed by the any of the authors.

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