Postural Assessment of Primary School Children working on Computers and the associated risk *Prachi Patel Visiting Faculty University Department of Resource Management SNDT Women s University, Juhu Mumbai India **Archana Bhatnagar Professor University Department of Resource Management SNDT Women s University, Juhu Mumbai India ***Manjit Kaur Chauhan Associate Professor University Department of Resource Management SNDT Women s University, Juhu Mumbai India Abstract The use of computers as a teaching tool is becoming disseminated in educationsystem, even in a developing country like India. The Government has emphasised for introducing computers in the education systems without giving proper guidelines for enhanced computer usage. The schools are clueless, so they invest in computers, software s and network infrastructure; but pays no attention to the ergonomic design issues and the needs of the students. Young children are operating adult size computer products on the workstations which are not made to fit them. Ergonomics comprise the scientific knowledge to ensure the comfort, safety, and efficacy of user. Therefore, the present study has as its purpose to investigate how computers are being used in schools of Mumbai. Computer workstations and the posture adopted by students while
working on them was studied. Table-chair combinations were inadequate for majority of the students with the seats height and desk height too high without the adjustability feature. Mismatch between the students dimensions and furniture dimensions were evident. Thus students were forced to assume awkward posture with majority having RULA Score of 5 or 6, thus increasing the postural risk. It can be concluded that by providing the students with proper computer workstation and teaching them appropriate guidelines on how to use this Adult tool will be helpful for children who are going to use computers more intensively than today s youths and workforce. Keywords: Primary School Children, Computers Workstation, Posture Risk. INTRODUCTION
Children and Computers: Most of the children from their birth are growing up in technologically rich environments in which they engage actively from an early age. So they are much more technically sound than the older generation were at their age, and they use computers and various other Information and Communication Technologies (ICTs), effortlessly. Data from the United States (De Bell & Chapman, 2003) indicate that 80% of the children are using computers by 5 years of age, whereas study from Australia (Starker et al., 2000) reported that 95% of children aged 5-14 use computers during or outside school hours. Computer is an essential part of almost all type of work, thus family members and the educational system actively promote the use of various technologies at home and schools respectively. For children, the age of exposure to computer and other ICTs is getting lower and lower with the usage hours per day increasing dramatically. As computers in the school system have become a mandatory item, the younger generation will continue to have more and longer computer classes throughout their schooling for educational and also entertainment purpose. Children have special needs, especially when working for a longer time on a device like computer which is designed for adult workforce. Studies suggest that schools too are making the same mistakes as office workplaces did in the 1980s, where computers are thrown on any flat surface thus creating very bad work habits (Mcgrane, 2001). These early exposures to adult-scaled input devices and mismatched furniture may place children at risk of injury both during their formative years and later in life. Computer, Workstation and Mismatch: Classroom learning environment have changed radically due to integration of various technology, but the physical environment has not changed to adapt them. School officials overlook the design safety of the computer centre in rush to get technology into schools (Mendels, 1999). The same old laboratory or nonadjustable classroom furniture is being used for computers by students of primary as well as secondary schools (Patel et al., 2013). The science of human factors and ergonomics has rarely been incorporated into the design of school furnishings. Children in modern societies are being increasingly exposed to computer use, and it will increase the risks of musculoskeletal injuries unless appropriate ergonomic guidelines are followed (Straker, 2001). The lack of adjustable computer furniture of school results in poor postures has been reported in Canada, USA and Australia (Greig et al, 2002; Oates et al, 1998; Zandvliet and Straker, 2001). The size and shape of computers, keyboards and pointing devices are also not tailored to children. (Bennett & Tien, 2003). Most children are now working for short periods of time on keyboards that are too high and incorrectly angled, looking sharply up at monitors (Oates et
al. 2000). While the risk is low, but likelihood of developing musculoskeletal problems can increase as they get older. Noro et al. (1997) reported mismatch between computer workstations and body size of school children. Zandvliet & Straker (2001) showed that lack of appropriate furniture in schools had resulted in poor postures by students and computer-related activities are risk factors for musculoskeletal pain (Hakala et al. 2006). As children are increasingly exposed to computer, it is possible that musculoskeletal injuries will also increase unless appropriate guidelines are followed (Straker 2001). Patel et al, (2013) found that computers are introduced in schools of Mumbai from standard 1st with an average of 2 4 students sharing one computer. Same computer furniture was shared by students of both primary and secondary school. Thus, Mismatch between the student s and furniture dimensions were evident, with seat and desk height too high than recommended levels. The number of complaints regarding student s visual or muscular discomfort during computer class was very low, and it could be related to the shorter duration of computer class. Posture adopted and the associated Risk: Oates, Evans and Hedge (1998) concluded that children were working in at risk postures, with keyboards and monitors too high, incorrect keyboard angle and legs dangling. Oates, et al., (2000) used the Rapid Upper Limb Assessment (RULA) and revealed that all six schools had computer-equipped classrooms in which students assumed postures associated with high risk for the development of musculoskeletal disorders. They found that seated posture improved when the workstation had the adjustable tilt down system. A study on high school students by Jones and Orr (1998) indicated that 28%, 40%, 41% reported hand discomfort, neck/back pain, and body pain, respectively, after computer use. Self-reported carpal tunnel syndrome was found in 4% of the sample. Evidence reveals that 30% to 60% of school-age children self-report having some form of musculoskeletal discomfort that they thought was exacerbated by computer use (Jacobs & Baker, 2002). In a similar study byszeto (2002) found that the eyes and the neck were the most common body parts that students complained of having discomforts, followed by upper limb regions. Positive association between the number of hours spent on the computer and musculoskeletal discomfort leading to neck shoulder pain and low back pain was found by Hakala et al. (2006). Jacobs et al. (2009) suggested that physical set-up and individual styles of using media has an influence over discomfort. Dockrell et al. (2010) investigated the effect of a school-based ergonomic intervention (i.e., computer education and workstation modification) on children s posture and discomfort using a pre/post-test study design including RULA, Visual Display Unit (VDU) checklist and Self-reported discomfort. They found positive response to the
intervention with significant changes between the pre-intervention and post-intervention scores. Force, repetition, and posture are well-documented occupational risk factors for musculoskeletal injury in adults, and children may be exposed to higher muscle loads and nonneutral postures due to their use of larger size devices, oversized furniture and more activation forces required to operate computers. In addition, the cumulative exposures to force and repetition among these children will be greater than any prior generation (Johnson & Blackstone, 2007).As the Number of children using computers and other ICTs is increasing. Thus, the aim of this study was to assess computer workstation of school children, its postures and related risk. OBJECTIVES To find out various postures adopted by primary school children while working on computer. To assess the student s posture in relation with the existing computer workstation and identify the possible risk. To provide simple guidelines for healthy computing at school. METHODOLOGY Sample Size and Locale: A total of 120 students (60 boys and 60 girls), aged 5 12 years, from 2 primary schools in Mumbai, using computers in schools were adopted. Fifteen subjects from 4 different grades (i.e., 1st, 2nd, 3rd and 4th) were selected from each school. Both schools were missionary schools and henceforth referred as School A - Boy s school and School M - Girl s school. Tools: Observation, Photographic and Checklist method was used. Observation Technique- Students posture, computer workstation & environment was observed. Photographic Technique- Digital camera used, to collect images of children working on computers. Checklist- A well designed checklist for assessing students posture in relation to computer workstation and its accessories was formulated, using the checklist given by Cornell University (1996), OSHA (1997) and Ontario (2004). The checklist was divided in three main sections General information Information like the gender, age, height, standard/grade, etc. of the respondent student.
Furniture and Equipment - This section aims to acquire information associated with the computer, accessories, pointing device, environment and furniture when the child interacts with the computer. Postural Assessment Third section aims to attain information about the various types of posture adopted by the student and problems that may exist as a result of the working posture of the child. The divergence in the Posture adopted by the students was studied using Photographic Technique and RULA technique was used to assess the postural risk. Formulation of categories for classifying the Posture: Based on 12 criteria s of neutral computer working posture (Table.4) given by OSHA and Cornell University, the students were assessed and were given 1 score for each of the criteria fulfilled. Thus the total score of each student would range in between 0 to 12, where 0 score would be of those student not fulfilling any of the neutral posture criteria s and 12 score would be of those student not fulfilling all the criteria s. Three categories of Posture (i.e., Poor, average and good) were formulated to classify the students based on their postural scores. The scores of each student out of total 12 criteria s was calculated and categorized. The students who score anywhere between 0-4 were classified as Poor, the students qualifying for 5-8 score were classified as Average and students scoring 9-12 was graded as Good. Procedure: A purposive sampling technique was used. As 2 to 4 students shared a computer, the student actually working on the computer was selected and their workstation and related posture was recorded. Photographs of the subject while working on computers from various angles were taken. Stature height was measured after the class. Teachers were interviewed. RESULTS AND DISCUSSIONS Students General Profile: The average age and height of both the boys and girls from school A and school M is about 7-8 years and 122.6 122.8 cm respectively. Table.1. General Information about the Students using Computers Parameters School - A [Boys: n = 60] School M [Girls: n = 60] Age (yrs) + SD (Range) 7.82 + 1.41 (5-12) 7.63 + 1.35 (5 10) Height (cms) + SD (Range) 122.6 + 10.65 (98 161.2) 122.83 + 10.89 101 149.6 Description of Existing Computer Workstation (Table 2 and 3)
Both the schools mostly provided wooden/plastic stools in computer classrooms, with very few chairs available in school-m. The desks in school A were science lab wooden tables with storage underneath. Whereas School-M had specially designed wooden tables with keyboard tray. Seat and desk heights of both the schools were compared to Neufert and BIS standards and were found to be above the recommended levels (Patel et al, 2013). Similar study byrocha et al, (2003) on 126 schools of São Paulo found that the use of computers in the 5th - 8th year of schooling was predominant with an average of two to three students per computer, and an average duration of classes of up to 2 hours per week. Computer furniture lack height adjustments. Table 2. Dimensions of Computer Seating (All the measurements are in centimetres) Standards Parameters of School School BIS Neufert Chair / Stools A M (5-13 yrs) (3-11 yrs) Stool Height (cms) 56-61 49 26 34 26 34 Chair Height (cms) 46 26 34 26 34 Remark More than recommended More than recommended Table 3. Dimensions of Computer Desk (All the measurements are in centimetres) Parameters of Computer School A School - M Remark(Comparing with Neufert Desk Mean (Range) Mean (Range) Standards) Table Height (cms) 82.7 (76 91.5) 80.25 (78.5-82) More than recommended i.e., 46-58 cms Floor Screen Height (cms) 122.6 114 More than recommended (116-131) (112-116) i.e., 77.5 102.5 cms Floor Keyboard Height 85.2 81.0 More than recommended (cms) (78.5-94 ) (78.5 83.5) i.e., 42.5 55 cms
Fig 1. Photographs of Computer Lab in School A Fig. 2. Photographs of Computer Lab in School M Postural Assessment Posture was assessed using 12 criteria s of neutral working posture adopted by the student while working on computers in classroom (Table.4). Assessment of Upper Extremity: Out of 120, only 20 students (16.67%) had head and neck upright in line with torso. 50 students (41.67%) was found with trunk perpendicular to the floor. This was because the desk height was too high compared to seat height, thus in order to view the screen the students were forced to sit erect with trunk perpendicular to the floor. Only 1 student was found with forearm, wrist & hand is below the sitting elbow/waist height. Assessment of Lower Extremity: Out of 120 students, only 32 students (26.67%) were found seating with thighs parallel to the floor, and about 38 students (31.67%) were found with their feet resting flat on floor, foot ring or footrest among which were 34 girls (56.7%) as they were standing or sitting on edge and operating the computer. Oates, Evans and Hedge (1998) too had concluded that children were working in at risk postures with keyboards and monitors too high, incorrect keyboard angle and legs dangling. Body Angle: It was also viewed from the table that only about 14 students (11.67%) were working in the recommended angle 90 0 100 0 of shoulder, elbow and wrist. It was very startling to discover the fact that around 104 students (86.7%) were assuming less than 90 degree angle for shoulder, elbow and wrist. This was majorly due to the high desk height with inappropriate sitting height. Mendels, (1999), too indicated that children are at risk for developing unhealthy postures and repetitive stress injuries due to keyboards and monitors set up higher than the recommended level leading to improper neck positioning and shoulder hunching; hence associated with neck and shoulder discomfort (Kroemer & Grandjean, 1997; Cook et al., 2000).
About 75 students (62.5%) were found working with trunk, hips and knees angle 90 0 100 0 and 52 (43.33%) with more than 100 0 Angle. It could be associated with students sitting erect and on edge of the seat to view the high computer screen. Only 29 students (24.17%) were found working with hips, knees and feet angle 90 0 100 0. Likewise 82 students (68.33%) adopted less than 90 degrees hip, knees and feet angle. This was because they were resting their feet on foot ring or on the legs of the stools. Table.4. Frequency of different attributes of neutral posture adopted by Students School-A School-M A + M 12 Criteria s of Neutral Posture while working on (n=60) (n=60) (n =120) Computers Total (%) Total (%) Total (%) Upper Extremity Head & neck upright (straight), in line with torso 11 (18.3%) 9 (15%) 20 (16.67%) Head, neck & trunk facing forward 16 (26.7%) 6 (10%) 22 (18.33%) Trunk perpendicular to the floor 25 (41.7%) 25 (41.7%) 50 (41.67%) Shoulders, Upper arms & elbow relaxed & in line with torso 12 (20%) 12 (20%) 24 (20%) Forearms, wrist & hand straight line while 16 (26.7%) working 15 (25%) 31 (25.83%) Forearm, wrist & hand is below the elbow/waist height 0 1 (1.67%) 1 (0.83%) Lower Extremity Thighs are horizontal / parallel to the floor 19 (31.7%) 13 (21.7%) 32 (26.67%) Lower legs vertical / perpendicular to the floor 8 (13.3%) 17 (28.3%) 25 (20.83%) Feet rest flat on floor, foot ring or footrest 4 (6.67%) 34 (56.7%) 38 (31.67%) Other General- Body Angle formed Shoulder, Elbow & Wrist- less than 90 0 47 (78.3%) 57 (95%) 104 (86.67%) - 90 0 100 0 (Recommended) 9 (15%) 5 (8.33%) 14 (11.67%) - more than 100 0 11 (18.3%) 12 (20%) 23 (19.17%) Trunk, Hips & Knees - less than 90 0 5 (8.33%) 0 5 (4.17%) - 90 0 100 0 (Recommended) 43 (71.7%) 32 (53.3%) 75 (62.5%)
- more than 100 0 20 (33.3%) 32 (53.3%) 52 (43.33%) Hips, Knees & Feet - less than 90 0 43 (71.7%) 39 (65%) 82 (68.33%) - 90 0 100 0 (Recommended) 17 (28.3%) 12 (20%) 29 (24.17%) - more than 100 0 17 (28.3%) 17 (28.3%) 34 (28.33%) A Thenon neutral or awkward posture hinders the blood circulation, creates discomfort and stresses the muscles ultimately leading to pain in the body part if assumed for longer duration. Thus it can be concluded that most of the children were not working in posture recommended by Hedge, 2000 based on angles of bent. In the present scenario this could be credited to the fact that the workstation design was responsible for students adopting awkward posture. The similar observations were made by Murphy, Stevenson, and Abdoli (2005) as they also used OSHA guidelines for their study. Classification of the posture (Table.5) Based on the 12 criteria s of neutral working postureadopted by the students the classification of posture was done into three categories i.e., poor, average and good. (Table.5).It was found that none of the students from both the school qualified for good category. It was alarming to find that 77.5% of students were falling under the poor category which fulfilled only 0 4 criteria and only22.5% of the total students were falling under average category fulfilling 5-8 criteria. Table.5. Classification of Posture based on postural score gained by student with respect to 12 criteria s of neutral posture School A(n = 60) School M(n = 60) A + M (n = 120) Classification of Posture Total (%) Total (%) Total (%) Poor (0-4) 44 (73.3%) 49 (81.7 %) 93 (77.5 %) Average (5 8) 16 ( 26.7%) 11 (18.3 %) 27 (22.5 %) Good (9 12) 0 0 0 Total 60 60 120 More number of girls was adopting poor posture and this could be due to the fact that even though the furniture of the school N was specially designed for the computer purpose, but the stools provided didn t match with the desk height. Whereas in boys school even though the desk height were higher compared to girls school, but the stools provided were also high, thus the boys scored comparatively good upper extremity score than girls (Table.5).Thus it can be
summarized that the children from both the schools are at the postural risk. Similar results were found byrocha et al, (2003) and Kanea, Pilcherb, legge (2006). Thus they will develop musculoskeletal problems in long run if some measures are not taken immediately. The workstation needs to be redesigned with the help of ergonomic guidelines for the students, so that risks are minimized, mismatch between the furniture and user is reduced and good posture is secured for the better future of these students. Table.6. Description of posture adopted by students and the RULA Scores. Number of students RULA Score Sr. Postures Photos of Photos of adopting such posture N adopted boys girls Total RULA o Boys Girls (%) Remark 5 1 19 21 40 (33.4) Further Investigationchange soon 2 11 11 22 (18.4) 6 Further Investigationchange soon 3 25 21 ` 46 (38.4) 6 Further Investigationchange soon 3 4 5 7 12 (10) Further Investigationchange may be needed
TOTAL 120 60 60 (100%) None of the above posture assumed by the students can be said completely GOOD, because it was observed that their postural score of RULA range from 3 6. Majority of students (71.8%) adopted posture that put them in the RULA final score category of 5 and 6, where further investigation as well as some change needs to be done soon. Similar study by Kelly et al. (2009) using RULA found that majority of the students posture while working on computers was in the Action Level 2 (65%) & AL 3 (30%) with significant increase in discomfort after class. Also if the student had an appropriate upper extremity posture, than they were found with legs either dangling or less of knee angle, thus with poor lower extremity and vice versa. The previous tables have already proven that the student had adopted poor posture and were found stretching, bending, twisting and tilting their body in order to view monitor screen and to operate the large size input device. This can also be correlated to the mismatch of the furniture dimensions with respect to the dimensions of the students. Thus many workstation design drawbacks facilitated the student to adopt poor or non neutral posture thus leading to postural discomforts which may eventually lead to Computer Related Injuries if sustained for an extended duration. MAJOR FINDINGS Related to Classroom Furniture Mismatch between the computer furniture, equipments and the student s anthropometry forced them to adopt awkward posture. Seat height and desk height was found to be inappropriate with respect to students height. Thus most of the students sitting the edge of the seat. The underside of the leg (thighs) was getting pressed while seating, with their legs either dangling or supported on legs of the high chair / stool. 50 % students hand resting on hard and sharp edge. Non adjustable furniture used by both primary and secondary school children. Related to Computer and input devices 2 to 4 students shared a computer, thus only few students had computer monitor and input devices within their easy reach Most of monitor placed above the sitting eye level. Input device were of adult sized and were place above the recommended waist height while sitting.
Related to Computer Accessories None of the schools provided wrist/ palm support, document holder, space for writing, space for keeping books/ bags and footrest. Related to Teachers Teachers were not aware about computer ergonomics and its application. Teachers were not having sufficient time to attend to all the students, as teacher student ratio was approximately 1:30. No health & Safety instructions, in use & arrangement of computer and its furniture were given to students and teachers. Students were made to sit roll number wise or randomly on computers. CONCLUSION Computers are being used increasingly by people of all ages. They are also becoming an important educational medium in the school system in the Asian countries. The schools are rapidly applying this technology in schools at very early age. The last generations of children barely touched computers and were therefore at little risk. Today skids will be exposed to prolonged periods of computer for all their childhood and also their adulthood. Unless we quickly develop some accurate and valid guidelines for the use of computers by children and see them implemented, we risk permanent scarring of a generation of children. So emphasis needs to be placed on teaching children how to properly use the computers and the workstations. Considering the magnitude of the problem, the study was undertaken to evaluate the existing computer workstation design for primary school children, amount of time spent and the posture adopted.the findings showed that due to the high seat height and desk height the students were forced to assume awkward and poor posture while working on computers. Student s feet were unable to reach the ground, thus many students had their legs dangling which may lead to an increase in tissue pressure on the posterior aspect of the thighs. Also it was commonly found that students placed their buttocks forward on the edge of the seat, especially while typing and working on computers. Due to high table height the students were forced to lift their arms and shoulders or bent their wrist while operating the input device. Over that, 2 to 4 students shared a computer, thus only few students had computer monitor and input devices within their easy reach. Twisting of neck and back, bending neck and back, stretching of trunk, extended hands, stooping, and leaning of back, neck, trunk or legs were commonly adopted. Even while not operating computers, student kept adopting awkward posture.
The findings of posture were quite alarming as it was observed that none of the student fulfilled all the criteria s of neutral working posture. On further analysis based on the classification of posture developed by the researcher confirmed that 77.5% of students adopted poor posture, indicating the postural risk and musculoskeletal problem in near future. RULA score also ranged from 5 6 for around 71.8% of population thus indicating further Investigation and changes required very soon. The duration of computer work often is relatively short. However, as computer use becomes more intense both at school and at home, the consequences of these mismatches between the furniture and the children and the resulting poor postures may become more serious. Teaching children good computer habits now will protect them from a future of painful injury. Tomorrow s Worker is in today s schools. Thus proper attention has to be paid on their workstation, which will help to prevent computer related problems in the future. RECOMMENDATION Recommendation for the Teachers Train Teachers about computer ergonomics including workstation setup, good working posture and good computing habits. If good computing skills are taught to students while introducing computers from early age, then it will help reduce the magnitude of computer related problems in later life. As students are not aware about their working posture, teachers can act as a mentor to teach them good computer habits and skills. Provide Proper sitting height Teacher should make student sit at an appropriate height (i.e., when typing on keyboard, the hands should be at or slightly below sitting waist height). If the hands are found to be above waist height, teacher can increase the seat height and provide proper footrest to support dangling legs. Recommendation for the Administrators Split level desk with a lower surface for placement of keyboard and mouse, and a higher surface for the monitor is a better option. Edges to rest the arm should be soft, smooth and rounded, Provide Kids size computer device, wrist rest/ arm supportand the document holders as per the requirement. Saddle type of stool can also be suggested in place of normal stool since they are height adjustable and also will keep the student in upright sitting posture, thus reducing the need of back rest. Different height of footring in the stool is a good option if footrest cannot be provided.
Fig 3.Simple and economic stools Fig 4. Adjustable, padded Chair with backrest Fig 5. Sit Stand Workstation Fig 6. Split level desk (Acknowledgement) I would like to thank all the students, whose cooperation made this study possible. Thanks to both the schools and their teachers for their support. Special thanks to my loving Mom and my family.
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