Fig 1 - available via license: CC BY
Content may be subject to copyright.
A conceptual model of smartphone usage, adapted from Dennerlein (2015). https://doi.org/10.1371/journal.pone.0203394.g001
Source publication
The number of smartphone users globally is rapidly increasing. This study aimed to assess the level of ergonomic risk to smartphone users, and to evaluate the correlation between any self-reported musculoskeletal disorders and the level of ergonomic risk. Thirty participants completed a questionnaire, tailored specifically for smartphone users, to...
Similar publications
AbSTRAcT
INTRODUCTION: Continuous static load during computer work results in the gradual development of pathological changes in the musculature of the upper back, neck, and arms.
OBJECTIVE: The aim of this paper was to identify problems in the area of the neck, shoulder area, and upper limbs associated with a static load on employees working on a...
Citations
... Metode penelitian menggunakan RULA (Rapid Upper Limb Assessment). RULA adalah alat pengukuran berdasarkan observasi yang umum digunakan untuk memberikan penilaian pada risiko postur kerja pengguna alat teknologi [18]. Terdapat 6 bagian tubuh yang diukur yaitu lengan atas, lengan bawah, pergelangan tangan, leher, batang tubuh/punggung, dan kaki [17]. ...
Musculoskeletal Disorders (MSD) merupakan keluhan kesehatan yang membutuhkan tindakan dan solusi perbaikan yang berkelanjutan. Munculnya MSD disebabkan oleh postur yang buruk selama melakukan kegiatan kerja. Pada penelitian ini dilakukan analisis terhadap postur kerja khususnya pada anak selama mengoperasikan smartphone. Kurangnya control diri pada anak menjadikan adiksi selama mengoperasikan smartphone, berpotensi pada postur kerja yang buruk, dan dilakukan berulang kali. Metode yang digunakan adalah RULA (Rapid Upper Limb Assessment). Postur yang dilibatkan dalam analisis adalah berdiri, duduk, dan berbaring. Hasil menunjukkan bahwa postur berdiri dan berbaring memperoleh total skor tertinggi yaitu 5, sementara postur duduk dengan skor 4. Hasil ini menunjukkan bahwa dibutuhkan investigasi tindak lanjut dan urgensi perubahan postur yang harus dilakukan segera. Ini menunjukkan bahwa, postur berdiri dan berbaring memiliki potensi yang buruk pada kesehatan pengguna jika tidak dilakukan perbaikan postur kerja sesegera mungkin. Dalam hal ini, disarankan untuk mengoperasikan smartphone dalam jangka waktu yang pendek/singkat pada postur berdiri dan berbaring. Kontrol dan penyesuaian dibutuhkan dengan adanya istirahat dan relaksasi sejenak selama mengoperasikan smartphone, sehingga dapat menghindari tekanan pada area tubuh tertentu.
... RULA is a screening technique that evaluates postural risk in IT device users and is observation-based. But it has not yet been used particularly with smartphone users (Namwongsa et al., 2018). Additionally, two posture risk quantification techniques were used: The first, an event-based strategy where the worst and most prevalent postures in a task are estimated, and the second, a time-based approach when posture patterns are derived from random samples of observed postures in the task (Bao et al., 2007). ...
Lean production has grown in popularity and has been adopted worldwide to strive for efficiency, waste reduction, and process optimization; it is realistic to expect lean production to continue to expand and evolve. While lean manufacturing may benefit organizations, it is vital to recognize that it can severely influence worker health and risk factors if not applied appropriately. Just-in-time manufacturing is related to shorter cycle times and resource savings. The increased work rate and insufficient recuperation time are linked to higher musculoskeletal risk symptoms. Value stream mapping (VSM) has enabled extended lean applications under triple-bottom-line (Social, Economic, and Environmental). The social components need to be addressed in favor of environmental and economic challenges. Previous studies indicate that using VSM might intensify work, putting workers at a higher risk of acquiring job-related musculoskeletal and psychosocial risks. The current study's version of VSM considers social support to enhance the working environment and lessen musculoskeletal and psychosocial risk factors. This article proposed a social-technical value stream mapping (Socio-tech VSM) technique and various possible societal metrics to improve social sustainability. To validate the method, a case study involving the PP Woven manufacturing business was used to document and report the results of the methodology's implementation, test it, and draw judgments regarding its efficiency. It contributes theoretically and practically to closing the gap on this long-ignored scope.
... The second feature integrated SmarTaxo [25], a taxonomy of 41 postures observed while engaging in primary smartphone activities, including texting, web browsing, watching videos, gaming, taking pictures, taking selfies, and making phone calls. This taxonomy was based on data from several studies that addressed the issue of posture when using a smartphone [13,22,[26][27][28][29][30][31][32][33][34]. SmarTaxo includes 27 postures -13 sitting postures, 6 standing, 7 lying, and 1 walking -associated with the above activities, except for phone calls. ...
... The total postural prevalence for all 41 postures ranged from 4.0 % for P Call 4 to 33.8 % for P Walk 1. This original result provides the postural prevalence of the users, which complements the analyses proposed in the literature for sitting, standing, and lying postures [31,36]. Three sitting postures (P Sit 2: 27.6 %, P Sit 7: 29.4 %, P Sit 8: 24.6 %), one standing posture (P Sta 2: 29.7 %), one lying posture (P Lie 5: 23.4 %), and the two walking postures (P Walk 1: 33.7 % and P Walk 2: 29.0 %) were particularly prevalent (+25 % of the sample) during the day. ...
... This elevation in risk is primarily attributed to significant extensions and rotations of the neck and trunk, which place users in awkward postures that elevate the risk of MSD.MSDs substantially. Similar high RULA scores have also been observed among smartphone users in sitting and lying positions [31]. Owing to the significant duration of use throughout the day, it is imperative to monitor the postures adopted and modify them as soon as possible in extreme cases to limit the risk of MSDs among users. ...
The long time spent on smartphones in awkward postures exposes young users to the risk of developing musculoskeletal disorders (MSDs). This study aimed to investigate 1) how the duration of smartphone use varies by the time of day and activities and 2) the risks of MSDs based on an analysis of the postures used when interacting with smartphones. A cross-sectional survey was conducted among 263 university students. The duration of smartphone use during a typical weekday was investigated over four times of the day and seven activities. After checking for normality, a nonparametric Friedman test was used to study the differences in the time spent using a smartphone according to the time of day and activity. Postural prevalence during weekdays was analyzed using a taxonomy called SmarTaxo, consisting of 41 postures. The Rapid Upper Limb Assessment (RULA) ergonomic score was chosen to assess the MSD risks associated with each posture.
Smartphone use was the highest in the evening (301.1 min; 95 % confidence interval [CI]: 277.4–324.8 min, p < 0.05). Texting (170.8 min; 95 % CI: 152.0–189.6 min) and watching videos (163.6 min; 95 % CI: 146.3–180.9 min) were the most common activities. Three sitting and two walking postures were primarily used in the morning (29.3–36.9 %), afternoon (27.0–44.4 %), and evening (28.9%–38.9 %). Standing postures were preferred in the morning and afternoon (36.9 % and 42.2 %, respectively), while one lying posture was widely reported in the evening (39.2 %). The RULA scores for these postures ranged from 3 to 4. However, four lying postures, often observed during the evening (frequency between 20.5 % and 37.6 % of the time), had RULA scores of 6. In conclusion, the study identified an existing MSD risk among smartphone users, especially with long durations of daily use. Special emphasis should be placed on addressing the reclining postures adopted during evening smartphone use, as they subject students to a significantly elevated risk of MSDs.
... Young people are commonly the major users of smartphones and are vulnerable to suffer health problems associated with prolonged use of these devices. The consequence of a very high rate of use in all situations of daily life leads to increased risk of MSD and joint pain [8]. Recent research has reported high prevalence rates of MSD ranging from 50 to 84% among smartphone users [9,10]. ...
... The originality of the questionnaire was to have integrated a wide range of postures covering the majority of activities performed with a smartphone, i.e. texting, web browsing, watching video, gaming, photos and selfies, and calling. They were obtained on the basis of works addressing the issue of postures when using smartphone [8,15,16,22,23,25,[27][28][29][30][31]. The synthesis of these works led to propose taxonomy of 41 postures called SmarTaxo (Table 1). ...
... The authors filled out a grid that provided the use rate of sitting (35.4%) and standing (64.6%). Namwongsa et al. found a repartition between sitting (73.3%) and lying (26.7%) postures among 30 students aged 18-25 [8]. Based on these works, only Kim's study [16] could provide a comparison with our results for sitting and standing postures. ...
Background
Musculoskeletal disorders (MSDs) are one of the most important problems among young smartphone users worldwide. Portability leads to a wide variety of postures during the different activities of the day. The objective evaluation of these postures coupled with ergonomic tools allows evaluating the level of MSD risk to which users are exposed.
Methods
The purpose was to investigate the effect of the time of day on the posture adopted during smartphone use among university students. The study was conducted through a cross-sectional survey of 263 university sports students. Four time of day, i.e. morning, afternoon, evening and night, and a taxonomy of 41 postures called SmarTaxo were considered. SmarTaxo included 18 sitting, 11 standing, 10 lying and 2 walking postures and their ergonomic score. After checking the normality of the data, a non-parametric Kruskal–Wallis test was used to study the effect of the time of day on the use duration of the different postures.
Results
The total mean duration use per typical weekday was 5.39 ± 2.19 h for males and 5.15 ± 1.60 h for females with maximal duration during evening. The average smartphone use durations were statistically longer in afternoon and evening for all sitting (9.44 and 9.22 min respectively, p < 0.05) and calling (3.38 and 3.33 min respectively, p < 0.05) postures. The longest duration for standing postures was recorded for afternoon (8.91 min, p < 0.05). The lying postures were significantly more present in evening (19.36 min). Some postures were more used during a time of day. The side-lying posture was used more in evening and has an ergonomic score of 6, i.e. a high MSD risk.
Conclusions
The survey showed that users are exposed to MSDs regardless of posture and time of day. Sitting postures are used more in the morning and afternoon while lying postures are used more in the evening. As long as the rate of use is so high (> 5 h per day), young people will remain highly exposed to MSDs.
... 17,23 These values imply a biomechanical/ergonomic risk, as has been reported in other long-duration static activities, for example, smartphone use. [31][32][33] Numerous studies have reported that significant neck and trunk flexion could be the cause of neck and lower back pain responsible for the occurrence of MSDs. These data largely could explain the high prevalence reported for these two areas among physiotherapists. ...
Objectives:
The aim of this work was to quantify the postures and to assess the musculoskeletal disorders (MSDs) risk in physiotherapists repeating a manual lymphatic drainage (MLD) over a three-month period. The underlying hypothesis was that there would be Generic Postures (GP) that would be repeated and could be used to more simply describe repetitive and long-duration complex activities.
Methods:
The posture of five physiotherapists performing five 20-min MLD at their workplace was captured by two cameras. From the recordings, the adopted postures were extracted every 5 s and quantified through 13 joint angles, that is, 6594 analyzed postures. Rapid Upper Limb (RULA) and Rapid Entire Body Assessment (REBA) were used to assess MSDs risks. A hierarchical analysis was used to define GP.
Results:
Seven GP were identified through mean values and standard deviation. GP ergonomic assessment showed a low to moderate MSD risk (RULA between 3 and 6 and REBA between 2 and 7). High neck (>20°) and trunk (>15°) flexion were observed for all GP. High shoulder abduction and flexion (>40°) were evidenced for GP3 to GP5. GP1 was the most used (34%) and presented the lowest ergonomic scores (RULA: 4.46 ± 0.84; REBA: 5.06 ± 1.75). GP3 to GP6 had frequency of between 10 and 20%. GP5, GP6, and GP7 obtained the highest ergonomic scores (RULA>5; REBA>7). All physiotherapists use different GP combinations to perform MLD.
Conclusion:
MLD could be described as a combination of GP. Ergonomic analysis showed that MLD exposes physiotherapists to low at moderate MSD risks.
... The ergonomics of the operation has been evaluated through the Rapid Upper Limb Assessment (RULA) method, which, developed by Corlett and McAtamney in 1993 [14], is a method of posture analysis that focuses on the upper body, but also includes the lower body [15]. It allows to assign both an operation's ergonomic overall score and specific scores for upper arms, lower arms, and wrists, together with posture of the neck, trunk, and legs, as well as another numerical rating for additional factors that strain the musculoskeletal system, such as repetitive action, static loading and force exertion [16]. Although this postural analysis process normally requires the intervention of an experienced ergonomist who observes workers' actions, a tool to automatically calculate these various risk indices on the basis of the information related to the kinematic of the worker's body (posture) is embedded in many software, including the employed one IC.IDO [17]. ...
System engineering (SE) methods and principles are nowadays widely adopted in the product development processes, especially in the industrial sector, where saving production time and costs are primary goals. This work describes an application of a particular SE methodology, the V-model-based design, in which the system development lifecycle is divided on the basis of a graphical V-shaped scheme, called V-model. Following this approach, a new concept of charging arm for Robotic Train Inspection Monorail (TIM) of Large Hadron Collider (LHC) at CERN (Conseil Européen pour la Recherche Nucléaire) has been developed. The current charging arm version is affected by several issues and limits that have led to the necessity of a new solution. Starting from the first stages of functional requirements (FRs) definition and decomposition (left side of the “V”), a new concept has been implemented, in order to be tested for its verification and validation (right side of the “V”). As part of the principles of SE, the process has been based on virtual models of the product and on virtual simulations of its operation, rather than on the realization of time-consuming and expensive physical models and tests, even if a final physical prototype has also been built and some physical operative tests have also been carried out on it. These tests have showed that the new product appears to fulfill each one of its FRs and overcome the limits imposed by the previous version. The future commissioning and operative tests in the real operating condition and location shall definitely validate the new product.
... Most symptoms were reported in the neck (84.6%), upper back/shoulder areas (65.4%) [18]. In Thailand, a few studies have surveyed the prevalence of WMSDs among university students and office workers and found that WMSDs were prevalent in the neck, shoulders, and lower back areas [19][20][21]. This may be due to inappropriate ergonomic posture, prolonged awkward posture, long working hours, or inadequate resting time. ...
Objective:
This study examined the prevalence of musculoskeletal disorders (MSDs) and their associated factors among 1st to 4th-year students at Walailak University who attended virtual classrooms for 1 week, 1 month, and 3 months.
Method:
A cross-sectional study was conducted among 382 students aged 18-23 years with no history of musculoskeletal disease or psychiatric disorder who had at least three months of virtual classroom learning. Statistical analysis was performed using chi-squared and Fisher's exact tests.
Results:
Most musculoskeletal abnormalities occurred in the shoulders, head and neck, and lower back at 1 week, 1 month, and 3 months, respectively. At one week and one month in virtual classrooms, the occurrence of MSDs among the students was correlated with psychosocial factors (p < 0.05), and at three months, MSDs were associated with personal factors such as body mass index and psychosocial factors (p < 0.05).
Conclusion:
Stress management for students should be implemented in virtual classrooms to prevent MSDs.
... The findings detected the high ergonomics risk, and it is often employed. The authors have reported that constructing a DL model based on RULA can be more successful (Namwongsa et al. 2018). Li and Xu developed a deep learning-based system for rapid upper limb assessment (RULA) using 2D posture. ...
The aim is to develop a computer-based assessment model for novel dynamic postural evaluation using RULA. The present study proposed a camera-based, three-dimensional (3D) dynamic human pose estimation model using 'BlazePose' with a data set of 50,000 action-level-based images. The model was investigated using the Deep Neural Network (DNN) and Transfer Learning (TL) approach. The model has been trained to evaluate the posture with high accuracy, precision, and recall for each output prediction class. The model can quickly analyze the ergonomics of dynamic posture online and offline with a promising accuracy of 94.12%. A novel dynamic postural estimator using blaze pose and transfer learning is proposed and assessed for accuracy. The model is subjected to a constant muscle loading factor and foot support score that could evaluate one person with good image clarity at a time.
... Several research studies have assessed the risk of the biomechanical overload of the musculoskeletal system based on a multimethodological comparative approach. Most of these studies analysed individual tasks in individual production sectors or contained descriptive analyses of the particular characteristics of risk-assessment methods [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. ...
... The analysis of the 2509 risk assessments conducted over these two decades reconfirmed the analytical peculiarities, which are difficult to compare, of the various observational assessment methods already highlighted in our previous experiences [23]. In agreement with the literature data [2][3][4][5][6][7][8][9], the specificities of the different methods for each risk factor investigated and for the anatomical districts of the upper limbs that they are used analyse are fundamental to the choice of the most suitable method for the analysis of a task and the study of preventive measures. ...
Background:
Several methods with which to assess the risk of biomechanical overload of the upper limb are described in the literature.
Methods:
We retrospectively analysed the results of the risk assessment of the biomechanical overload of the upper limb in multiple settings by comparing the application of the Washington State Standard, the threshold limit values (TLV) proposed by the American Conference of Governmental Industrial Hygienists (ACGIH), based on hand-activity levels (HAL) and normalised peak force (PF), the Occupational Repetitive Actions (OCRA) checklist, the Rapid Upper-Limb Assessment (RULA), and the Strain Index and Outil de Repérage et d'Evaluation des Gestes of INRS (Institut National de Recherche et de Sécurité).
Results:
Overall, 771 workstations were analysed for a total of 2509 risk assessments. The absence of risk demonstrated for the Washington CZCL, used as the screening method, was in good agreement with the other methods, with the sole exception of the OCRA CL, which showed at-risk conditions in a higher percentage of workstations. Differences in the assessment of the frequency of actions were observed among the methods, while their assessments of strength appeared to be more uniform. However, the greatest discrepancies were observed in the assessment of posture.
Conclusions:
The use of multiple assessment methods ensures a more adequate analysis of biomechanical risk, allowing researchers to investigate the factors and segments in which different methods show different specificities.
... In future, it will be possible to upload data collected by IMU directly to the manufacturer and then receive a RULA evaluation. Since RULA-PP was used more frequently in older studies [37][38][39], it was not possible to compare the results with RULA-IMU until now. The trend to generate ergonomic analyses by IMUs will continue, and RULA-IMU is a good measure to obtain a risk analysis by RULA without the need to involve an observer. ...
Background:
The Rapid Upper Limb Assessment (RULA) is used for the risk assessment of workplace-related activities. Thus far, the paper and pen method (RULA-PP) has been predominantly used for this purpose. In the present study, this method was compared with an RULA evaluation based on kinematic data using inertial measurement units (RULA-IMU). The aim of this study was, on the one hand, to work out the differences between these two measurement methods and, on the other, to make recommendations for the future use of the respective method on the basis of the available findings.
Methods:
For this purpose, 130 (dentists + dental assistants, paired as teams) subjects from the dental profession were photographed in an initial situation of dental treatment and simultaneously recorded with the IMU system (Xsens). In order to compare both methods statistically, the median value of the difference of both methods, the weighted Cohen's Kappa, and the agreement chart (mosaic plot) were applied.
Results:
In Arm and Wrist Analysis-area A-here were differences in risk scores; here, the median difference was 1, and the agreement in the weighted Cohen's kappa test also remained between 0.07 and 0.16 (no agreement to poor agreement). In area B-Neck, Trunk, and Leg Analysis-the median difference was 0, with at least one poor agreement in the Cohen's Kappa test of 0.23-0.39. The final score has a median of 0 and a Cohen's Kappa value of 0.21-0.28. In the mosaic plot, it can be seen that RULA-IMU had a higher discriminatory power overall and more often reached a value of 7 than RULA-PP.
Conclusion:
The results indicate a systematic difference between the methods. Thus, in the RULA risk assessment, RULA-IMU is mostly one assessment point above RULA-PP. Therefore, future study results of RULA by RULA-IMU can be compared with literature results obtained by RULA-PP to further improve the risk assessment of musculoskeletal diseases.
