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 Table of Contents  
ORIGINAL ARTICLE
Year : 2022  |  Volume : 29  |  Issue : 3  |  Page : 221-227

Mobile phone usage among Nigerians: Risk factors for musculoskeletal injuries and preventive strategies


1 Department of Physiotherapy, Faculty of Clinical Sciences, College of Medicine, University of Lagos, Lagos, Nigeria
2 Department of Biomedical Engineering, Faculty of Basic Medical Sciences, College of Medicine, University of Lagos, Lagos, Nigeria

Date of Submission05-Apr-2022
Date of Decision28-May-2022
Date of Acceptance20-Jun-2022
Date of Web Publication22-Jul-2022

Correspondence Address:
Ayoola Ibifubara Aiyegbusi
Department of Physiotherapy, College of Medicine, University of Lagos, Lagos
Nigeria
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/npmj.npmj_92_22

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  Abstract 


Aims: The increase in the usage of hand-held devices (HHDs) and smartphones (SPs), especially in Nigeria has resulted in an upsurge of musculoskeletal complaints. The aim of this study was to determine the incidence and risk factors for musculoskeletal injuries due to mobile phone usage among Nigerians and the preventive strategies. Materials and Methods: This study involved 630 male and female participants above 18 years old who were purposively recruited across designated study centres in public places. The instrument used was a questionnaire specifically designed to suit the Nigerian culture and environment and developed from previously validated questionnaires. Data were exported to Statistical Computing Programming R version 4.0.5 for analysis and Chi-square was used to compare the characteristics of those who experienced injury using SPs/HHDS and those who did not. Independent variables with a 95% confidence level and P < 0.05 in the multivariate model were considered statistically significant. Results: The most common daily use of SPs/HHDS by the participants was phone calls (98.4%) followed closely by social networking (96.0%) while the occupation and educational level of the participants had statistically significant (P < 0.05) impact on musculoskeletal injuries. The type of mobile device and the time spent using these devices were also significant (P < 0.05) risk factors for injuries. Some self-treatment strategies adopted by the participants were all significantly (P < 0.05) associated with reduction of musculoskeletal discomfort. Conclusion: The occupation, educational level, the types of mobile devices and time spent using the devices were risk factors for musculoskeletal injuries.

Keywords: Hand-held devices, mobile phones, musculoskeletal injuries, risk factors, smartphones


How to cite this article:
Akinbo SR, Aiyegbusi AI, Okafor UA, Balogun OJ. Mobile phone usage among Nigerians: Risk factors for musculoskeletal injuries and preventive strategies. Niger Postgrad Med J 2022;29:221-7

How to cite this URL:
Akinbo SR, Aiyegbusi AI, Okafor UA, Balogun OJ. Mobile phone usage among Nigerians: Risk factors for musculoskeletal injuries and preventive strategies. Niger Postgrad Med J [serial online] 2022 [cited 2022 Aug 13];29:221-7. Available from: https://www.npmj.org/text.asp?2022/29/3/221/351729




  Introduction Top


Hand-held mobile devices (HHDs), are devices which are compact and portable enough to be held and used with one or both hands for communication and entertainment purposes.[1] These include smartphones (SPs), tablets, Ipads, I-phones and portable gaming devices.[2] In recent times, the number of SP users and the duration of usage have increased tremendously because of their use for both occupational and leisure activities.[3],[4],[5]

The combination of repetitive movements, poor posture and over-use of mobile phones (MPs) for texting or playing games without taking rest breaks, can cause injury to the nerves, muscles and tendons in the fingers, hands, arms and neck, which if ignored, may lead to long-term damage.[6],[7] Prolonged use of a SP, which has a smaller visual display terminal (VDT) than that of a tablet PC or computer, can cause severe damage to the neck and surrounding structures due to increased lower neck flexion angles compared with the use of a tablet PC.[8] In addition, the use of SPs while walking has a negative effect on the lumbar spine.[9]

Previously, the major health concern with regard to MP use was cancer, such as brain tumours or acoustic neuroma.[10] Currently, the exposure patterns have shifted to addictive use, resulting in psychological impact, safety issues and musculoskeletal symptoms.[11],[12] Prior studies had reported that in Nigeria, the recent high incidence of musculoskeletal disorders (MSD) may be connected to the widespread use of computers and MPs.[13],[14] Prior to 2001, the country had <500,000 telephone lines but as at December 2021, there were 304,048,720 connected mobile lines in Nigeria with 195,128,265 being active.[15]

It is, therefore, notable that the impact of SP use on the health and musculoskeletal system is fast emerging as a cause for national concern. The burden of this contemporary communication technology, therefore, necessitates studies on its prevalence and impact on the musculoskeletal system of the Nigerian population.[16] The aim of this study was to establish the incidence and risk factors for MSD and injuries associated with the use of SP and other hand-held mobile devices (HHD) and the impact of self-reported preventive strategies across a general population of adults in Lagos, Nigeria.


  Materials and Methods Top


Subjects' selection

The data for this study were collected between March and June 2021 and involved (630) participants who were recruited by convenience for this study. A minimum of fifty participants were recruited from each of the selected twelve designated study centre across different public places. Areas with the highest concentration of SP and HHD usage were designated as study centres and included health centres, civil service secretariats, tertiary institutions, major sports/recreation centers, major motor parks, Airport terminals and major markets/supermarkets.

Participants recruited for this study were male and female adults 18 years and above with no previous musculoskeletal injuries, surgery and/or disability involving the upper limbs and the spinal column. The purpose of the study was clearly explained to all the participants and their approval and signed informed consent were obtained.

The questionnaire

The instrument used for this study was a questionnaire which was adapted and developed from the Orebro Musculoskeletal questionnaire,[17] the disabilities of the arm and shoulder questionnaire[18] and the DUTCH Musculoskeletal Questionnaire.[19]

The questionnaire included graphical illustrations and was designed to suit the Nigerian culture. It was thus easy for respondents who were not very proficient in English language to understand the questions. Section A collated the socio-demographic information of the respondents. Section B was on the types and mode of usage of SPs and other HHDs. Section C was on the types and location of injury/discomfort sustained in the usage of SP/HHDs. Section D gave information on the severity and duration of injury in body parts, while Section E collected information on the management and prevention strategies against injury/discomfort.

Methods

The questionnaires were administered to respondents in each of the study centres by two research assistants and collected by hand. Participants who were not very proficient in the English language were assisted. Ethical approval was sought and obtained from the Health Research and Ethics Committee of the College of Medicine, University of Lagos with approval number CMUL/HREC/1026/19.

Determination of sample size

Using Cochran's by Israel, (1992)[20] formula for sample size determination.



Where n = minimum sample size for statistically significant survey.

z = The standard normal deviation, usually set at 1.96 (95% confidence level).

P = 30% prevalence of MSDs associated with mobile devices from other studies 18.5% to 67%.[21]

For P = 18.5%-:

d = Degree of accuracy set at 0.05

q = 1–p = 1–0.185 = 0.7



Data analysis

Entry, coding and cleaning of questionnaire data were done using Microsoft Excel 365 (Windows 10 Pro). Data were exported to Statistical Computing Programming R version 4.0.5 for the analysis.[21] Descriptive statistics were presented, as the median and interquartile range for the variable age (age is not normally distributed), text, frequency distribution tables and percentages for categorical variables. The Chi-square test or Fisher's exact test was used to compare the characteristics of those who experienced an injury/discomfort using SPs/HHDS and those who did not. Independent variables with a 95% confidence level and P < 0.05 in the multivariate model were considered statistically significant and presented with an adjusted odds ratio with a 95% confidence interval.[22]


  Results Top


A total of 576 (91.4%) completed questionnaires were eligible for analysis out of 630. Excluded from the study were 19 individuals that had missing data, while an additional 35 underage participants below 18 years were removed. There were 326 (56.6%) males and 250 (43.4%) females. Participants' mean age was 21.3 ± 1.9 (range 18–25) years and the mean BMI was 22.1 ± 3.2 (range 17.1–40.8) kg/m2. [Table 1] shows some demographic profile of the participants and their association with discomfort among the participants. The analysis shows that only the occupation and educational level of the participants had a significant impact on musculoskeletal discomfort. It is shown in [Figure 1] that the most common daily use of SPs by the participants was phone calls (98.4%) followed closely by social networking (96.0%). [Table 2] presents the association between discomfort and position and time spent using SP/HHDs and it is seen that majority of the participants reported 5–8 h daily of continuous sitting and working while most of them exercised between 1 and 2 h weekly. Furthermore, the type of mobile device and the time spent using these devices had a significant impact on injuries and discomfort [Table 3]. [Table 4] and [Table 5] present the treatment and preventive strategies used by the participants against injuries. Although, many participants used more than one treatment method (51.6%) and more than one prevention method (49.2%), majority of them (42.8%) did not consult any physician for SP/HHDs-related musculoskeletal discomfort. In [Table 5], self-treatment of massage, exercise, use of ointment, drugs, spiritual and combination of more than one method of treatment were all significantly (P < 0.05) associated with the prevention of musculoskeletal discomfort.
Table 1: Association between sociodemographic characteristics and musculoskeletal discomfort in participants

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Figure 1: Common daily use of smartphones/hand-held devices. SM: Social media, PG: Playing games, WV: Watching videos, CPV: Capturing photos and videos, LAHF: Listening to audio hand-free, Text: Texting messages, Read: Reading

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Table 2: Association between discomfort and position and time spent using smartphones/hand-held devices

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Table 3: Association between discomfort and type and duration of use of smartphones/hand-held devices

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Table 4: Distribution of management and prevention strategies against injury/discomfort associated with usage of smartphone/hand-held devices

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Table 5: Multiple logistic regression showing the association of treatment strategies and prevention of pain in the usage of smartphone/hand-held devices

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  Discussion Top


In view of the upsurge in the use of MPs and other HHDs in Nigeria, this study investigated the risk factors for musculoskeletal injuries across a general population of Nigerians. This is very pertinent as each new generation of MP comes with more in-built functions which results in increased exposure and use of MP functions with the likelihood of greater exposure to repetitive messaging and gaming activities. Prior studies had investigated this in different subsets of the population, but our investigation included the different strata of the adult population, across age groups and occupations. This is important to identify modifiable risk factors and therefore, develop preventative measures based on the different patterns of SP use in various age groups and at different life stages as some age groups may be more at risk of SP addiction than others.[23]

It was observed that the majority of the respondents used their mobile devices mostly for social media activities, calls and texting, followed by reading in that order. This was expected as the demographic characteristics of the study population showed that most of the users of mobile devices were in the age group of 18–45 years that represents the studying and working population age bracket. SP use has become the dominant cultural reality of contemporary university students as they are used during classes, studying and executing assignments.[24],[25] A prior study had even reported that students' achievement increases significantly when they use mobile learning devices, including SPs, and students are increasingly optimising its potential.[26],[27] In addition, Mobile technology enables people to work during their leisure time and also facilitates private communication in the workplace.[28] This explains why educational attainment and occupation were significantly associated with musculoskeletal injuries among the respondents as previously reported that a habitual pattern of increased muscle activity in the neck and shoulder region is a common phenomenon among office workers with chronic neck and shoulder pain.

Our findings showed that while the number of active phone lines and mobile devices used had no impact on injuries, the type of mobile device used by the respondents had a significant association with injury and discomfort. Most of the respondents in this study used SPs which have been reported to have small VDTs, thereby compelling individuals to look at their phone's small monitor and perform repetitive movements usually in an awkward posture for a prolonged duration, which can result in MSDs.[29],[30] To corroborate this, a recent study identified the size of the SP, the predominant purpose of SP usage, position preferred while using the SP, and level, at which SP is held while using the device as significant risks for musculoskeletal pain and further logistic regression analysis showed that the size of the SP was significantly associated with musculoskeletal pain.[31] This is because a SP has a smaller VDT than a tablet PC or computer and so produces greater neck flexion.[32],[33] A prior study also found that the prolonged use of a SP leads to a greater lower neck flexion than the prolonged use of a tablet PC, thus prolonged use of SPs can cause severe damage to the neck and surrounding structures as supported by a recent systematic review that reported evidence of neck flexion, frequency of phone calls, texting and gaming contributing to musculoskeletal complaints among mobile device users.[8],[34]

Our study also showed that the position commonly assumed when using HHDs and the duration of continuous sitting while working, significantly contributed to the development of discomfort. This finding is in concordance with that of Berolo et al.[35] which showed that the total time spent using a SP was significantly associated with pain in the neck and shoulder. This may be attributed to bad SP posture, which involves leaning over a cell phone as previously reported to be more pronounced in children who used portable PCs than those who used desktop computers, thus resulting in increased muscle activities of the trapezius and the sternocleidomastoid muscle.[36],[37] Furthermore, from our findings, the average and longest time spent daily using mobile devices had a significant impact on the prevalence of injuries and discomfort. Most of the respondents who complained of discomfort spent an average of 2–4 h daily using their devices and 5–8 h daily in continuous sitting while working. The disparity could be because people may not be able to accurately estimate the time spent on activities except there are objective means to determine that such as suggested by Spink et al.[38] They recommended that investigating the relationship between mobile HHD use and musculoskeletal symptoms and other health outcomes may consider using a logging application to better determine exposure time and other risk factors.

However, past research has shown that computer use for over 4 h/day would contribute to increased risk for MSDs.[39],[40] Our results show that over 60% of the respondents spent above 4 h daily on average using their mobile devices and they constituted about 64% of those that reported injuries/discomfort. This can be attributed to SP addiction as reported by a prior study that SP addicts used their phones for 5.4 h/day compared with normal SP users, who used their phones for 4 h/day. The study also identified the addiction risk by age and reported it to be 25.5% for teenagers, 15% for people in their 20s and 8.2% for people in their 30s.[41] Seeing that the population of respondents below the age of 30 years was about 60%, underscores the high incidence of those addicted to SP use.

Interestingly, the predominant purpose of SP usage and position preferred while using the SP can act as protective factors for musculoskeletal pain.[31] Our findings showed that the self-adopted treatment and preventive strategies by the participants had a significant impact in reducing musculoskeletal pain and discomfort, though despite this, the incidence of discomfort was still very high among them. It may, therefore, be necessary to educate the populace on preventive strategies against musculoskeletal injury and discomfort such as suggested by Shin and Zhu[42] that users of SPs/HHDs hold the device just below eye level, take a break every 10 min, and stretch the muscles around the neck and shoulders.


  Conclusion Top


We conclude that the occupation, educational level, the types of mobile devices and time spent using the devices were risk factors for musculoskeletal injury and discomfort which was very high among the participants despite the self-adopted treatment and prevention strategies used.

Financial support and sponsorship

This study was funded by the University of Lagos, Central Research Committee: Grant number (CRC NO: 2018/28).

Conflicts of interest

There are no conflicts of interest.



 
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  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5]



 

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