Association between the usage of Smartphone as the risk factor for the prevalence of upper extremity and neck symptoms among University students: A cross - sectional survey based study.

 

Deivendran Kalirathinam^1*, Manoj Abraham Manoharlal², ChongLi Mei³, Chong Kar Ling³, Thomas Wong Yong Sheng³, Albin Jerome⁴, Mahadeva Rao US⁵.

¹Faculty of Health Sciences, School of Rehabilitation, Universiti Sultan Zainal Abidin, Kuala Nerus, Kuala Terengganu, Malaysia.

²Saveetha College of Physiotherapy, Saveetha University, Saveetha Nagar, Chennai, Tamil Nadu, India.

³Faculty of Health Sciences, University Tunku Abdul Rahman, Selangor, Malaysia.

⁴School of Physiotherapy, Faculty of Allied Health professions, AIMST University, Semeling, Malaysia.

⁵Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu, Malaysia.

 

ABSTRACT:

Background: The usage of smartphone played a significant role in everyday life especially among students. Concern has risen universally of possible musculoskeletal symptoms among smartphone users due to excessive use. Objective:  To determine the prevalence of neck and upper extremity symptoms among University students who were using a smartphone. Methods: A cross – sectional survey using self – administered questionnaires were conducted on 250 undergraduate students from one of the leading university in Malaysia. Six out of 250 participants (2.4%) were excluded as they were not a smartphone user. The number of participants from two faculties, namely Faculty of Medical and Health Sciences  (FMHS)  and Faculty of Accountancy and Management (FAM) were determined with stratified random sampling using Kish Leslie sample size formula. Results: The frequency of six measures of smartphone use was ranked from highest to lowest in order: Internet browsing and E – learning (85.20%), making phone calls (78.30%), texting and emails (77.00%), music, video, and pictures (75.40%), gaming (51.20%) and scheduling (32.80%). Out of 244 participants, 49 (20.1%) of the smartphone users were found to have developed some degree of upper extremity and neck symptoms. The prevalence of neck symptoms was the highest with 44 (18.03%) sufferers, followed by right shoulder symptoms (13.93%) and left shoulder symptoms (11.07%).   Despite the symptoms experienced, only   5 (10.20%)   participants   received   treatment while   30 participants (61.22%) claimed that they continued using the smartphone during these episodes. Conclusion:   It is postulated that there is a positive relationship between smartphone usage and prevalence of upper extremity and neck symptoms. Recommendation: It is high time to disseminate the basic education on proper usage related to ergonomics is warranted to the university students to increase their awareness.

 

 

INTRODUCTION:

The smartphone is a handheld device that is capable of performing the function of a laptop and a hand phone. Even though it is compact and small, it can perform various tasks such  as  Internet browsing,  mobile mail,  games,  media players, phone calls, text – editing capabilities, and much more. Therefore, its usage is now becoming a great importance in everyday life and a universal practice, especially among students. It has been found in numerous studies that it was difficult for people to part with their gadgets even for a second. However, device usage has both pros and cons^[1,2]. The smartphone is defined  as  ―a  mobile phone  that performs  many of  the functions of a computer, typically having a touchscreen interface, Internet access, and an operating system capable of running downloaded apps ^[3].As the use of smartphone has become more significant nowadays due to the various functions it offers to the users, more and more study was conducted to investigate its pattern of usage.

 

There  was   a  study  investigating  the  health  effects  of  using smartphone and portable electronic devices among Hong Kong people with result showed that out of the 1049 people surveyed, 70% of adults and 30% of children and adolescents have reported musculoskeletal symptoms in different parts of the body related to the use of electronic devices^[4].Meanwhile, in Malaysia, the prevalence of musculoskeletal symptoms of the upper extremity and neck was relatively high among college students leading to the incidence  of these  symptoms to  be described  as common. Complaint of symptoms in the  distal part  of the  upper extremity  (most top complaint of symptoms was in thumb followed by elbow, wrist, fingers, hand and forearm) were more when compared with the proximal part (shoulder and arm)^[5,6,7] .

 

However, the exact cause of these symptoms was unknown, and multiple risk factors had been suggested such as physical activity, improper ergonomic of smartphone device, gender, age, excessive use of computer and smartphone ^[7,8].

 

The incidence of musculoskeletal disorders arise due to prolonged forceful, low amplitude and repetitive use of handheld devices. This was supported by a study which revealed mobile phones that promote the use of the thumb or only one finger were associated with a higher prevalence of musculoskeletal disorders. A case was reported which described a 48 years old woman complaining of weakness, paresthesia, and pain in the bilateral hand. Hence she was diagnosed with bilateral De Quervain tenosynovitis which was associated with excessive use of the text messaging feature on a cellular telephone. Following this, new term emerges such as Blackberry thumb, SMS thumb and text neck^{[5,9 -11]}.

Also, postures (sitting or standing) and the type of mobile phone task (holding the phone versus texting) have an effect on muscle activity and thumb positions. Compared to talking, muscle activity was higher during texting. The thumb is placed in abduction and flexion during texting compared to adduction and extension when making phone calls with its range of movement differ according to the size of the phone and orientation of the keys. Females compared to males had higher muscle activity in the extensor digitorium muscle and the abductor pollicis longus muscle when entering SMS messages and tended to have greater thumb abduction, higher thumb movement velocities and fewer pauses in the thumb movements. The sustained posture and the repetitive movement of the thumb is a predisposing factor to musculoskeletal disorder ^[12].

 

In the current study, the focus will be on determining the association between the usage of the smartphone as the risk factor for the prevalence of upper extremity and neck symptoms among University students.

 

METHODOLOGY

A Cross – sectional survey as the observation of the prevalence of upper extremity and neck symptoms was made based on a single examination of a cross – section of one of the leading Malaysian University students at one point in time. The human ethical approval for this study was obtained U/SERC/48/2014.Sample size, Using a sample size formula by Kish Leslie for cross sectional studies ^[13]. The calculated sample size N = (1.96)2 (0.185 × 0.815) / 0.052 = 232 students. However, 250 participants were selected based on the inclusion / exclusion criteria. The study was conducted over 7 weeks.

 

Inclusion criteria: University students who had been using smartphone for a period minimum 1 year.

Exclusion criteria:

1. All the participants who had not had smartphone related injury less than six months ago or were suffering from any inflammatory, degenerative, or neuromuscular condition of the upper extremity and neck affecting the activities of daily living.

 

2.  Participants involved in regular recreational activities involving repetitive movements of the upper extremity and neck for the past three months.

 

DATA ANALYSIS

The questionnaires collected were screened to exclude any incomplete questionnaire or participant that fell under the exclusion criteria as well as participants who did not fulfill the inclusion criteria. Data entry was then carried out using Microsoft Excel before analyzed using SPSS software.  The descriptive statistic, Chi-square test, Independent samples T-test, and Mann-Whitney test was performed by using this software to analyze the data collected.

 

RESULTS:

Response Rate

A total number of three hundred and fifty questionnaires were distributed to students. The response rate was 99%. However, the attrition rate was 30% due to questionnaire not being filled completely or participants fell under exclusion criteria. Two hundred and fifty questionnaires were left completed and according to Kish Leslie sample size formula, the amount was sufficient for this study as the minimum number of participants required based on the calculation of the formula was two hundred and thirty-two. The self – administered questionnaires were distributed in venues such as the library, cafeteria, north and south lobby on the campus as students were not rushing and they were more willing to take part in the survey. On the other hand, the number of students from the Faculty of Medicine and Health Sciences (FMHS) and Faculty of Accountancy and Management (FAM) were determined using stratified random sampling to prevent sampling error and to compute the effective sample size for each faculty. Besides that, as the students were approached on one – to – one basis, it was easier to check for any error or mistake made by students when answering the questions in the questionnaire. In this case, the response rate is more valid and useful for further research.

 

_{Table 1. Demographic characteristics of the participants}

Variable	n	%	Mean (SD) Age
Gender Male Female	81 169	32.4 67.6	20.67 (1.40)
Course FMHS FAM	53 197	21.2 78.8
Year of study Year 1 and 2 Year 3 and 4	166 84	66.4 33.0

 

_{Table 2. Position, average hours, period, and type of Smartphone use.}

Variable	n ( %)	Median (IQR)	Mean (SD
Smart Phone user Yes No	244 (97.6) 6 (2.4)
Computer usage Yes No	164 (67.2) 80 (32.8)
Dominant hand Left Right	30 (12.3) 214 (87.7)
Hand use on smartphone Left Right Both Left and Right	11 (4.5) 83 (34.0) 150 (61.5)
Average hours use per day		5.00
Years of smartphone use		(5.00)	3.13 (1.74)
Position of use Sitting Frequently Sometimes Rarely	186 (76.2) 53 (21.7) 5 (2.0)
Standing Frequently Sometimes Rarely	33 (13.5) 152 (62.3) 59 (24.2)
Supine Frequently Sometimes Rarely	57 (23.4) 99 (40.6) 88 (36.1)
Prone Frequently sometimes rarely	35 (14.3) 101 (41.4) 108 (44.3)
Side lying Frequently Sometimes Rarely	43 (17.6) 91 (37.3) 110 (45.1)
Other Frequently Sometimes Rarely	4 (1.6) 2 (0.8) 238 (97.5)
Six Measures of smartphone use Texting, email Frequently Occasionally	188 (77.0) 56 (23.0)
Scheduling Frequently Occasionally Rarely	80 (32.8) 163 (66.8) 1 (4.0)
Internet browsing, E – learning Frequently Occasionally	208 (85.2) 36 (14.8)
Phone calls Frequently Occasionally	191 (78.3) 53 (21.7)
Music, video, pictures Frequently Occasionally	184 (75.4) 60 (24.6)
Gaming Frequently Occasionally Rarely	125 (51.2) 117 (48.0) 2 (0.8)
Presence of symptoms Yes No	188 (77.0) 56 (23.0)
Treatment received Yes No	5 (10.2) 44 (89.9)

 

_{Smartphone users}

Among 250 participants who took part in the survey, there were 244 (97.6%) smartphone users, whereas only 6 (2.4%) participants were non – smartphone users. Out of the 244 participants who were using smartphone, 164 (67.21%) of them used computer daily for more than 3 hours _{while 80 (32.8%) were not.}

With respect to position when using smartphone, 186 (76.2%) participants frequently used smartphone in sitting while 53 (21.7%) participants claimed that they sometimes used smartphone in sitting with remaining of 5 (2.0%) participants admitted of rarely using it in the mentioned position. Thirty-three (13.5%) students claimed they frequently used smartphone in standing, while 152 (62.3%) claimed sometimes and 59 (24.2%) rarely used it in standing.

 

Fifty-seven (23.4%) participants frequently used their smartphone in supine position, while 99 (40.6%) claimed sometimes and 88 (36.1%) rarely used their smartphone in supine position. Besides that, 35 (14.3%) students frequently used their smartphone in prone lying, while 101 (41.4%) students claimed sometimes and 108 (44.3%) participants rarely used smartphone in prone lying. Meanwhile, 43 (17.6%) participants frequently used the smartphone in side lying while 91 (37.3%) participants claimed sometimes and 110 (45.1%) rarely used smartphone in this position. For other positions of use such as squatting, only 4 (1.6%) of the participants frequently used it in the squatting position while 2 (0.8%) participants claimed sometimes and the remaining 238 (97.5%) participants claimed they rarely used in another position.

 

Overall, the position of smartphone use topped highest on sitting (76.2%), followed by supine (23.4%), side lying (17.6%), prone (14.3%), standing (13.5%) and lastly other position of use (1. 6%).In relation to handedness, 214 (87.7%) participants were right– handed while only 30 (12.3%) of them were left– handed. When inquired about hand use while using smartphone, 150 (61.5%) participants answered that they used both left and right hand, 83 (34.0%) participants stated that they used right hand while 11 _{(4.5%) participants  admitted to using left hand.}

 

Table 3. Smartphone usage and its related upper extremity and neck symptoms

Variable	n (%)	Median (IQR)	Mean (SD)
Neck symptoms Yes No	44 200	18.0 82.0
Left shoulder symptoms Yes No	27 217	11.1 88.9
Right shoulder symptoms Yes No	34 210	13.9 86.1
Right    elbow    and    lower    arm symptoms Yes No	14 230	5.7 94.3
Left    elbow    and    lower    arm symptoms Yes No	9 235	3.7 96.3
Left hand symptoms Yes No	7 237	2.9 97.1
Right hand symptoms Yes No	22 222	9.0 91.0
Average symptoms duration			10.0 (28.0)

 

Upper extremity and neck symptoms

In the study (table 3), it was found that 44 (18.0%) smartphone users experienced some degree of neck symptoms while the remaining 200 (82.0%) participants did not report of any neck and upper extremity symptom. Left and right shoulder symptoms were also reported in the questionnaire, with 27 (11.1%) respondents having left shoulder symptoms and 34 (13.9%) having right shoulder symptoms out of the 244 participants. Among the 244 participants, 14 (5.7%) smartphone users reported of right elbow and lower arm symptoms while the remaining 230 (94.3%) users did not suffer from any symptoms. Nine (3.7%) users also reported of the left elbow, and lower arm symptoms with the remaining 235 (96.3%) users did not. From the study, it was found that 22 (9.0%) participants experienced some degree of right-hand symptoms, while the remaining 222 (91.0%) participants did not report any symptoms. The study also showed that 7 (2.9%) participants said of left-hand symptoms, while 237 (97.1%) of participants do not have any left-hand sign.

 

Average symptom duration

On average, the median duration of symptoms experienced by participants per day was 10.0 minutes (Interquartile range = 28.0 minutes).

 

In this era of advanced telecommunication, it has been found that smartphone usage has increased tremendously and it is still increasing each year. A study conducted by Malaysian Communication and Multimedia Commission (SKMM) concluded that there was only about 12% - 14% of smartphone users from 2010 to 2011 and the figure four folded in 2016. Besides, there were about 35% of the respondent in that study intended to switch to smartphone from the common handphone. In this present study, the percentage of smartphone users among students was as high as 97.60%. This study was conducted to determine the prevalence of upper extremity and neck symptoms  with the  usage of  smartphone among  students. From the survey carried out, it was found that the prevalence of upper extremity and neck symptoms was 20.1%. This result was similar to a study regarding the prevalence of cumulative trauma disorders in cell phone users in which the overall prevalence was found to be 18.5% ^[5].

 

 

Prevalence of upper extremity and neck symptoms among age group

In this study, the mean age of participants was found to be 20.67 years old ranging from 18 to 29 years old. The study also showed that there was significant in prevalence on the left-hand symptoms among the participants with a mean age of 21.71 years old with a  significant value  of  0.045.  A study conducted by Williams et al found that there was greater fatigue rate when voluntary work was performed with the non – dominant hand rather than the dominant hand. However, the overall statistics show not much of a difference in the mean age between those having symptoms and not having symptoms, this can be further explained by a study conducted by Lindstrom et al that there is significant lower maximal voluntary contraction (MVC) and the endurance of muscles in older adults compared to younger adults ^[16]. Another study also suggested that the musculoskeletal disorder is not solely dependent on age and the tendency for injury is more associated with the demand and physical work capacity ^[17].

 

Prevalence of upper extremity and neck symptoms among genders.

The overall statistical analysis does not show much significant on the incidence of upper extremity and neck symptoms. However, the prevalence of right elbow and lower arm symptoms (0.038), as well as right-hand symptoms (0.049), were found to be significant. Generally, women were at a higher risk of developing musculoskeletal symptoms with the higher predominance of symptoms found in wrist and          hand ^[18,19].

 

In this study, the average years of smartphone use were 3 years. The overall pattern of usage of smartphone by the participants showed that  the  percentage  of  usage  top  the  highest  on  Internet  browsing  and  E  – Learning at 208 (85.2%) participants, followed by making phone calls, sending messages (texting and emails), and multimedia (music, video and pictures) which was almost equal to 191 (78.3%), 188 (77%), and 184 (75.4%) participants respectively, while gaming was moderately used at 125 (51.2%) and lastly scheduling was the least used at 80 (32.8%) participants. This is in accordance to a study conducted by Berolo et al which found that participants spent most of the time on Internet browsing while scheduling was the least ^[15]. In the study conducted by Ayub et al, it was found that students browse the internet to obtain relevant information and materials to complete assignments and projects. However, the usage of internet on academic aspect was moderate with remaining of the time students uses it for social and entertainment purposes ^[20]. It was also found that high prevalence of  musculoskeletal  symptoms of  the upper  extremity occurred in adults who used the smartphone for a long duration exceeding 3 years which was relevant to result proposed as the participants were found to have been a using smartphone for an average of 3 years. As mentioned earlier, Williams et al concluded that there was greater fatigue rate when voluntary work was performed with the now – dominant hand ^[21].

 

Prevalence of upper extremity and neck symptoms with handedness

Based on the current study of upper extremity and neck symptoms on the handedness  of  smartphone,  it  was  found  that  the  prevalence  of  left  hand symptoms was the higher within the left dominant participant than the right dominant participants at 0.012. This is in line with the study conducted by Clerke,A. and Clerke, J. which found that the right hand is generally stronger than the left hand in which may cause the left hand to be more prone to injury than the right hand^[22].

 

With regards to the high significant value of prevalence of symptoms in the dominant hand, there was a study conducted by Walker – Bone et al. stating that pain was usually bilateral in nature, or more prominent in the dominant arm. The neck and upper limb pain were usually simultaneous and display a symmetrical pattern of involvement ^[23]. This is in accordance with the present study findings where significant prevalence of neck (0.047), left shoulder (0.023), and right shoulder (0.013) symptoms were found on bilateral handedness smartphone user.

 

Prevalence of upper extremity and neck symptoms with position of use

High prevalence of upper extremity and neck symptoms in various positions of smartphone usage was found in this study. It was reported that there were significant prevalence of neck and right upper extremity (shoulder, elbow and lower arm, and hand) symptoms in various positions. Significant prevalence of neck symptoms was found in participants who use their smartphone in side lying and supine at 0.001 and 0.007 respectively. Most individual believe being in supine does not strain the neck or may prevent neck symptoms, however study has shown that there was no advantage lying in supine in the prevention of neck symptoms instead this position was significantly associated with increased incidence of symptoms experienced ^[24]. When an individual is in side lying, the gravitational pull the spine away from its naturally straight position therefore leading to the spine bending towards the lying surface causing neck pain ^[25]. The current study also revealed that there was significant prevalence of the right shoulder symptoms in supine (0.009) and prone (0.031). Besides that, right elbow and lower arm symptoms showed significant prevalence in prone (0.015), side lying (0.013) and other position of used (0.024). Lastly, right hand symptoms showed significant in supine (0.038), prone (0.035) and side lying (0.038).It was suggested that the high prevalence of right shoulder symptoms was due to high percentage of participants in this study were right hand dominant at 87.7%. A study found that majority of the individuals tend to lie on their side of dominant hand, therefore there is a causal relationship between the right shoulder pain and lying on the right shoulder because there was a high proportion of right hand dominant participants as well as a high prevalence of right upper limb pain participants ^[26]. This can be explained theoretically by the findings of lying on the shoulder causes higher sub acromial pressure ^[27].

 

Significant prevalence of the upper extremity such as right hand, right elbow and lower arm on both supine and prone position can be due to awkward posture, unsupported and static position which restrict the blood flow to the muscles hence damaging it and causes these symptoms ^[28-30].

 

IMPLICATION OF STUDY:

This is a preliminary study in which the data can be used for further research to identify the risk factors, preventive measures, causes and many other factors relating to musculoskeletal and neurological symptoms with smartphone usage. Awareness can be brought noticed to all the students on the detrimental effects of prolonged and improper posture usage of smartphone which will eventually lead to musculoskeletal symptoms. The data obtained in this study suggest the relevant agencies to take adequate measures to educate the end users on its ill effects of prolonged and improper postured usage of smartphone.  Smartphone manufacturers can also be pressure to further improve   their   smartphone ‘s   ergonomics   to   reduce   the   stress   and   strain experienced by the muscles with prolonged smartphone usage.

 

LIMITATION OF STUDY:

The main limitation of this study was that the cross – sectional design does not provide the cause – and – effect relationship.  This was  because the  cross  – sectional study provides only a snapshot of frequency and characteristics of the neck and upper extremity symptoms in a limited population who are smartphone users, at a particular point of time. The findings might be differed from those obtained in the current study than when it is conducted again in the future.

 

Next, the number of students from the Faculty of Medicine and Health Sciences (FMHS) and Faculty of Accountancy and Management (FAM) was determined using a stratified random sampling method. However, gender was failed to be stratified due to the information regarding number of male and female students for each faculty was not available. As a result, the total number of female respondents (67.6%) was relatively higher than male  respondents  (33.4%). Gender can serve as a confounding factor as previous research studies have shown that females are more likely to develop musculoskeletal symptoms of neck and upper extremities compared to males.

 

Last but not least, the size of smartphone was not taken into consideration in this research. Sharan et al. revealed that measurement of thumb postures during Short Messaging Service (SMS) texting was affected by the size of the mobile phone and movement axes of the thumb. The thumb is more likely to develop musculoskeletal symptoms when it worked near the extreme range of motion ^[10].

 

RECOMMENDATION FOR FUTURE RESEARCH:

A case – control study should be carried out for future research to obtain a more well – validated cause and effect relationship. Besides that, a range of risk factors can be identified for upper extremity and neck symptoms experienced. Next, male and female participants should be more equal in number to generate more accurate results as different gender may have different tolerance to symptoms. In addition, the size of smartphone should be stated by participants to find out  if  there  is  any  association  between  ergonomic  factors  of  phone  with prevalence of symptoms.

 

CONCLUSION:

Hence, preventive measures should be taken to reduce the prevalence of upper extremity and neck symptoms among students.  Participants should be taught to adopt a good posture on smartphone usage such as sitting on a chair with back support with the addition of pillow to be placed on the lap to support the arms. Several exercises should also be done such as chin tuck which helps counteract the poor posture, stiffness and to increase blood circulation within the muscles.

 

In this study, most students use the smartphone for internet usage as well as texting.  This will greatly induce upper extremity and  neck symptoms among students in the long run, hence it is suggested that participant uses computer or laptops to browse the internet if they are required to use it for a prolonged period as this can prevent fatigue and injury to a single muscle. The usage of stylus should be encouraged when using smartphone for activities such as texting or drawing, which can greatly reduce the stress experienced by the muscles of the hand.

 

 

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