Introduction

In the world of this century, types of available computer technologies have become diversified. The use of these technologies is rapidly increasing in all areas of life.

In addition to leading countries such as Australia, America, and England, Turkey has also made considerable investments for classroom educational technology tools. The Ministry of National Education (Turkey) has been conducting a project known as the Movement to Increase Opportunities and Technology (FATİH Project), where the classes will receive smart boards, students will receive tablet computers, and classes will be enriched with the use of e-books. FATİH Project aims to send all state schools spanning from preschools all the way to high school level a total of 620,000 smart boards, while tablet computers will be distributed to 17 million students and approximately one million teachers and administrators.

As children are still physically developing both in terms of MSK system and posture, if there is a possibility of negative long-term consequences of the IT devices they use, on their physical or visual health, it should be investigated. At a point, even the children themselves think that technologies such as tablet PCs can have negative effects on health (Dündar and Akçayır 2014). When we consider the fact that school children spend nearly 30 % of their day at school, use of mobile technologies at schools for educational purposes may have negative impacts on MSK health if not used carefully. In the literature, it has been argued in several studies that children’s use of mobile technologies has been associated with MSK discomfort (Harris and Straker 2000; Greig et al. 2005; Sommerich et al. 2007; Straker et al. 2008b), especially neck discomfort and high prevalence of MSK discomfort is thought to indicate a high risk of MSK disorders (MSDs). Hedge (2005) defines MSDs are soft tissue injuries of connective tissues, muscles, or nerves. This risk of MSDs is not of course the only reason to study posture, MSK activities, and MSK discomfort among children using laptops or tablet computers for educational purposes. As the field of educational ergonomics suggests, education process can be affected positively by improving the designs of, by suggesting guidelines of use for, or by simply identifying possible problems related to, mobile technologies used by children for educational purposes.

This study searches the literature to identify published studies that investigated posture, MSK activities, and possible MSK discomfort among children using mobile technologies (laptops or tablet computers) for educational purposes. Given the importance of the MSK health of children, namely future workforce, relatively few studies have adequately examined the posture, MSK activities, and possible MSK discomfort among children using laptops or tablet computers for educational purposes or studied the adverse effects of these technologies on developing children. In his book, Extra Ordinary Ergonomics, Kroemer (2005) has underlined the unfortunate fact that the ergonomics of children and teenagers is generally underemphasized and disregarding such populations in designing phase makes their lives harder. In short, this review provides an overview of studies to date on MSK impacts of new technologies such as computers, laptops, and tablet computers.

Therefore, this review is important for pointing out the research gaps in this field, and identifying areas for future studies.

After a short look at the physical impacts of the use of computers on the MSK system of children, the study presents the studies to date on guidelines for information and communication technology products use, with a special focus on children-specific guidelines and a short review of studies focusing on physical impacts of laptops and tablet PCs on the MSK system to date. The study focuses on physical impacts of laptops and tablet PCs on the MSK system of children and on studies comparing different technologies such as laptop, desktop, and tablet computers with each other in terms of physical impacts of these technologies to musculoskeletal health with a special focus on children subjects. Despite the fact that there are no risk assessment tools yet designed specifically for children, this work involves a section dedicated to such studies, which used one or more risk assessment tools in studies with children subjects. The study concludes with a summary of the gaps in the literature concerning the studies on musculoskeletal impacts of the mentioned technologies on children, especially school children using such technologies for educational purposes and identifies the likely directions of future research.

Method

The review included steps of preliminary reading phase, identifying the search key words, identifying the priority databases to be searched, conducting the literature search, categorizing the articles according to relevance, and writing the review.

Literature Review

In the results of the search, there are studies focusing on attitudes, opinions, and preferences of teachers or children using computers and mobile technologies for educational purposes, as well as researches focusing on positive and negative aspects of mobile technologies in respect to academic achievement (Ng and Nicholas 2009; Dündar and Akçayır 2014; Alvarez et al. 2011; Lowther et al. 2003). These studies are not included in the review in detail, because this review will be focusing on physical impacts of these technologies. It should be noted that benefits of information technology’s use for education purposes should be complemented with optimal environment for physical and physiological discomfort, which is the subject of field of Ergonomics. In other words, increase in learning productivity or better learning opportunities should not be achieved at the expense of MSK health.

Use of conventional PCs by children has been of interest to researchers for many years. Researchers has been trying to quantify muscle activities, to examine the physical impact of the use computers on the MSK system of children, to identify or propose risk factors for development of MSDs, or to compare paper-based tasks with computer-based ones in order to quantify the variation in muscle activity regarding the computer use of children. (Oates et al. 1998; Leaser et al. 1998; Ciccarelli et al. 2006; Breen et al. 2007; Maslen and Straker 2009; Straker et al. 2008a, b; Straker et al. 2009a; Brink et al. 2009; Harris 2010; Zovkic et al. 2011; Dockrell et al. 2010). However, there are very few studies about new mobile technologies such as laptops and tablet PCs and risks associated with their use by children for educational purposes.

The smaller size of technologies such as laptops, tablet PCs, and pocket PCs makes them advantageous to some extent. However, there are issues like, smaller screen size not displaying all parts of webpages arising the need to scroll to view the complete page or multitouch movements used in operating tablet PCs. This additional scrolling need or multitouch movements may add a further cognitive load or muscle stress to the user. In this literature review, focus will be on studies trying to figure out possible physical impacts of such technologies on children, primarily on school children.

Physical impacts of use of laptops or tablet PCs used for educational purposes should be of concern because they occur during critical periods of children’s skeletal growth.

Guidelines for Children’s Information and Communication Technology Products Use

Hedge (2005) notes that in addition to improving the design of the computer workplaces of children, adults should also educate them regarding the safe use of computers in order to help them develop lifelong protective habits. For adults to educate children in an appropriate manner, there is a need for guidelines for children’s computer use.

Maslen and Straker (2009) underlines the fact that there are limited numbers of experimental studies of children’s computer use, and thus, the guidelines for children’s computer use are still not developed in the form of international standards like adults. Harris et al. (2005) argued that the relationships between risk factors and MSK outcomes may be different for children than adults because children and adult MSK systems are different; purpose of children in using IT is different; the physical IT environment in school or home environments are not generally adjustable; children have potential of adopting awkward postures for prolonged periods even when they experience discomfort. In order to support the development of recommendations for effective use of IT by children, the researchers presented a framework for a model of IT use by children and MSK problems.

It should be noted that given the differences in size and input devices, even if guidelines for children’s computer use were developed, they would not be fully applicable for laptop or tablet PC use of children. However, to form a basis for such guidelines, the studies of developing guidelines for computer use are also important at this point.

Following a broad literature review highlighting the evidence of both positive and negative effects of computer use for children, Straker et al. (2009b) presented a set of guideline principles to minimize the risk of adverse effects of computer use specifically for children. Towards the development of the children-specific guidelines, the gaps identified through the literature review were also filled (Straker et al. 2008a, b). Among the six general principles presented, the last one is on wise use of computers in terms of facilitating appropriate physical development by eliminating potentially damaging physical stresses. Offered set of guideline principles constitutes a basis for further detailed guideline studies. However, as mentioned above, if not used with an external keyboard and mouse, the evidence-based guidelines offered do not specifically apply for laptop and tablet computers. Straker et al. (2010) published children-specific evidence-based physical guidelines for the wise use of computers aiming to facilitate appropriate physical development of children. The recommended guidelines are based on a literature review regarding the physical aspects of child–computer interaction. Although the guidelines recommended have not been supported with randomized controlled experiments, it forms a good basis for future studies.

Physical Impacts of Laptops and Tablet PCs on the MSK System

Physical impacts of mobile technologies on the MSK system are not yet well documented and studied like physical impacts of desktop computers. This section is dedicated to summarize the studies on physical impacts of mobile technologies, mainly laptops and tablet computers.

On the basis of recent technological trends, Korpinen et al. (2013) conducted a study to determine the possible relation between self-reported neck symptoms such as aches, pain, or numbness and the use of computers, portable computers, or cell phones. In the study, 6,121 responses were collected from 15,000 questionnaires, which were sent to working age Finns. When studying the respondents with symptoms in the neck, this questionnaire study of Korpinen et al. (2013) pointed out that the respondents having neck symptoms very often also had some additional physical and mental symptoms such as exhaustion at work or sleeping disorders. In addition to this finding, the results of the study also supported the hypothesis of use of different types of computers may increase the risk of developing neck pain.

Briggs et al. (2004) analysed the sitting posture of school children interacting with books and new information technologies such as laptop and desktop computers. They concluded that the type of information technology used is interacted with the students’ posture.

Straker et al. (1997) evaluated postural constraints, discomfort, and performance associated with laptop use. The results suggest that inflexibility of the laptop screen leads to increased neck and head flexion, and/or increased shoulder and elbow flexion to reach a higher keyboard, which potentially results in MSK discomfort. Besides, 75 % of the laptop users tested reported visual discomfort after a 20 min use of laptop. However, when performance indexes achieved by the laptop and desktop computer users were compared, although not significantly different, laptop user performances were slightly more improved than the desktop user performances. Similarly, Werth and Babski-Reeves (2012) assessed posture associated with laptops, netbooks, and tablets on two different work surfaces. Results of the experimental study indicate that tablet computer use and/or working at a nontraditional workstation like a sofa result in degraded postures. Especially, using tablet computers leads to degraded wrist and neck postures, which may increase risk for injury or illness development for these parts of the body.

Pereira et al. (2013) evaluated the effect of tablet size, orientation, grip shape, texture and stylus shape on productivity, biomechanics, and subjective usability and fatigue associated with holding the tablet with just left hand. This study confined its examinations among users with small hands, because subjects with smaller fingers are likely to be exposed to higher risk of using handheld devices. Results of the study suggest that on the basis of usability, fatigue, and biomechanics, the small- or medium-sized tablets should be preferred for the cases of holding the tablet with one hand. When compared with small- or medium-sized tablets, large tablets had higher forearm muscle activity, shoulder moment, and wrist extension. Both Lozano et al. (2011) and Young et al. (2012) emphasized that the nondominant arm (the one holding the tablet PC) experiences increased shoulder flexion, and muscle activity compared to dominant arm (the one performing the data entry). In their study, which involved 15 adult tablet users, Young et al. (2012) also underlined the fact that the use of tablet computers is associated with high head and neck flexion postures when compared to conventional desktop computers and suggested that head and neck posture can be improved through use of cases to support the tablets.

As mentioned before, the physical impacts of tablet computer use on the MSK system are not well documented yet. Aiming to provide designers with objective measures of the impact of gestures and configurations of tablet on MSK system, Lozano et al. (2011) studied the effect of some multitouch interactions (a set of free stroke gestures representing one and two finger type of interactions) and concluded that multitouch interactions have impact on the entire hand shoulder system. In addition, the research underlines the fact that holding the tablet creates high muscle activation levels for the nondominant arm.

Up to this point, the studies under this section were not focusing on children’s use of mobile technologies. At the time of this research, only a few published studies were found that discussed the physical impacts of laptop and tablet PC use of children in educational environments. Henceforth, the studies summarized in this literature review shall be focusing on physical impacts of laptop and tablet PC use by children.

Physical Impacts of Laptop Use by Children

Harris and Straker (2000) conducted a two-phase descriptive study and identified the potential physical consequences of laptop use by school children. First phase of the study involved a survey conducted among 314 school children, and the second phase was interviewing and observing a group of twenty school children using their laptop computers. The study suggests that children’s use of portable computers with prolonged poor postures leads to MSK discomfort. In other words, the study found an association between MSK discomfort and duration of exposure to IT. It is also an interesting and important finding that 26 % of the participating children reported that they would still continue on with the task even after experiencing discomfort. The findings of the study point out that necessary ergonomic considerations such as typing postures and keyboard height are not generally considered at schools, and this potentially increases the risk of MSDs developing in children.

Although their study is not directly related with laptop use by children, Straker et al. (1997) also underlines the fact that laptops are increasingly being used in educational settings, and therefore, children are likely to be exposed to prolonged poor postures during critical periods of their skeletal growth.

In their study dealing with ergonomic issues related with computer use of elementary school students, Zovkic et al. (2011) point out that laptop ergonomics is far from ideal because laptops do not have height adjustment options and the space between the keyboard and the screen is too small. Low position of a screen may lead to unconscious leaning forward and thus neck and/or back pain.

Physical Impacts of Tablet PC Use by Children and Adolescents

Being one of the first studies to investigate ergonomic aspects of tablet PCs in relation to student use, Sommerich et al. (2007) conducted a study, which included collecting data from students via a two-part questionnaire and a computer-use monitoring software. A total of 77 students actually participated in the study with consent. The two-part questionnaire aimed to drive statistical conclusions on students’ experiences with the tablet PCs, their attitudes about tablet PCs, physical discomfort associated with use of tablet PCs, and temporal and task-driven usage patterns of tablet PCs. The results of the questionnaire indicate that students’ experiences are infrequently problematic and students’ attitudes are generally positive towards the tablet PCs, and eyes, neck, head, right hand/wrist, upper, and lower back are the body parts that students potentially experience discomfort associated with tablet PC use.

Although not directly related with tablet PC use by children, the work of Pereira et al. (2013), which considered tablet design features on biomechanics among users with small hands, should also be mentioned here. Because, although the overall hand size of subjects was still bigger than the hand size of children, the study results can give an idea on children’s use of same technology.

There are very few studies evaluating tablet PC use by children; work of Straker et al. (2008b) is one of those studies. The researchers compared seated children using tablets placed on a table with use of desktop computers. The details of this study can be found under “Comparison of Tablet Computer and/or Laptop Use with Other Options and/or Each Other” section. Results of the study summarizes that tablet PC use was associated with more neck and trunk flexion, more flexed and elevated shoulders, and greater muscle activity around the neck.

Comparison of Tablet Computer and/or Laptop Use with Other Options and/or Each Other

Briggs et al. (2004) tried to find a relation between physical posture and the type of information technology being used by analysing the sitting posture of school children interacting with three IT types that are commonly found in schools: a desktop computer, a laptop computer, and a book placed flat on the desk. In this study, the task of children during the study was limited to reading (with no input process). The research results concluded that the type of information technology used influences students’ postures, and a lack of variation can lead to serious and long-term injury. The study summarizes the results as follows: Children reading from books had more head and neck flexion, and a greater gaze angle when compared to children reading from laptops, while children reading from laptop computers had more head tilt, neck flexion, and a greater gaze angle when compared to children reading from a desktop computer. Interestingly, reading from laptop computers resulted in head and neck postures closest to resting postures. Given these conflicting kinematic and muscle activity evidence reached during the study, the researches decided that definitive recommendations could not be made based on these results.

Greig et al. (2005) conducted a laboratory study measuring cervical erector spinae (CES) and bilateral upper trapezius (UT) muscle activity in school children to investigate the effects of different forms of information technology such as books, laptops, and desktop computers. Muscle activity data were collected using Surface EMG. The study concluded that CES muscle activity in the book and laptop setups were found to be significantly greater than that in the desktop setup. In contrast to the expectations, although head/neck flexion of the book setup is the greatest, the associated muscle activity was not greatest (Table 1).

Table 1 Summary of researches on musculoskeletal impact of desktop, laptop and tablet use for educational purposes
Full size table

Straker et al. (2008b) compared a tablet computer-based task, a desktop computer-based task, and a paper-based task performed by young children in order to assess the differences in postures and muscle activities. The researchers reported that tablet use was associated with more neck and truck flexion, more flexed and elevated shoulders, and greater muscle activity around the neck. However, computer tasks require less variable postures when compared to tablet and paper-based tasks. This study suggests that as tablet computers are associated with a more flexed and asymmetrical spine and a more elevated and flexed shoulder that the conventional desktop computer, tablet computer use is likely to pose a greater risk of injury or discomfort compared with conventional computer use. On the other hand, as the tablet computer use is associated with a greater postural variation and muscle activity when compared to conventional desktop computer use, this may offset the nonneutral postures and higher muscle activity associated with tablet use.

Risk Assessment Tools for Children

There are no risk assessment tools yet designed specifically for children; however, Rapid Upper Limb Assessment method has been utilized frequently in the literature (Leaser et al. 1998; Oates et al. 1998; Breen et al. 2007; Dockrell et al. 2010). RULA is known to be a subjective observation method of posture analysis, which does not require previous skills in observation techniques.

In their study investigating children’s posture and discomfort associated with computer use, Breen et al. (2007) chose RULA as an appropriate, cost-effective, reliable postural evaluation method. Dockrell et al. (2010) also utilized RULA for evaluating the postures. In all studies mentioned in this section till now, reliability of the method was assessed by inter-rater agreement percentages.

Dockrell et al. (2012) investigated both inter-rater and intra-rater reliability of the use of RULA with children. Their results suggest that RULA is a moderately reliable tool for being used in assessment of school children’s computing postures. Findings of the study also imply that RULA may be more suitable to assess older children’s computing posture. Higher intra-rater reliability results when compared to inter-rater reliability results imply that making a series of assessments by the same person would be more consistent. The results also show that there may be a learning effect, which highlights the importance of adequate training and practice before using it. This finding actually contradicts with the assertion of Chen et al. (2014), which is summarized below.

Chen et al. (2014) investigated if experience is a factor contributing to differences in the results of the Rapid Upper Limb Assessment method. The aim of the study includes investigating the differences between results of RULA of a child using mobile ICT (in the home environment) by experienced and inexperienced assessors. As the study concludes that there were no significant differences between the RULA scores of experienced and in-experienced assessors, it can be concluded that RULA can be used in postural risk assessments regardless of the assessor’s experience.

Conclusions and Future Work

This review constitutes the first part of a multistage project, the overall purpose of which is to investigate the possible problems associated with the tablet PC or laptop use of children for educational purposes. We have searched the literature and reviewed the published studies about posture, MSK activities, and possible MSK discomfort among children using laptops or tablet computers and studies addressing physical impact of mobile technologies by school children for educational purposes.

It is clearly obvious from the search results that the resources investigating MSK outcomes of laptop or tablet PC use of children are really scarce. There are only a few studies that investigated ergonomic aspects of laptop/tablet PC use by children for educational purposes, and there are no specific risk assessment method proposed for children. Although some methods developed for adults are considered to be reliable for children as well, there is no doubt that the working conditions (classroom environment) and physical needs of children are different than adults’. There exist some guidelines for children using conventional PCs; however, guidelines for mobile technologies such as laptops or tablet PCs have not been developed yet. More experimental studies of children’s laptop and/or tablet computer use to identify the potential problems can be helpful to lead to development of the relevant guidelines for children.

Considering the widespread use of mobile technologies in adults, adolescents, and children, it is of importance to also investigate mobile technologies other than laptops and tablets (which were of focus in this review), such as mobile telephones. The musculoskeletal risk factors of mobile phone users especially children users have remained untouched till now. Further research with children that involves assessment for musculoskeletal outcome measures is also recommended.