Changes in the Thickness of Median Nerves Due to Excessive Use of Smartphones

Abstract

Abstract.[Purpose] The present study was intended to examine the effect of excessive use of smartphones on the carpal tunnel and median nerve in the wrist. [Subjects and Methods] A questionnaire was used to determine the degree of addiction to smartphones in 125 normal adults who used smartphones; then, ultrasonography of the median nerve, Phalen's tests, and reverse Phalen's tests were conducted on the subjects.[Results] Based on the results of the experiment, the thickness of the median nerve did not change in relation to duration of smartphone use per day, duration of continuous smartphone use, periods of the use of smartphones, or the degree of addiction; however, statistically significant shortening of time to wrist tingling was identified in the Phalen's tests and reverse Phalen's tests conducted to examine clinical symptoms. [Conclusion] In conclusion, excessive use of smartphones may act as a cause to trigger carpal tunnel syndrome due to pressure on the carpal tunnel in the wrist joint; thus, precautions are necessary when using smartphones.

Effects of electronic device overuse by university students in relation to clinical status and anatomical variations of the median nerve and transverse carpal ligament

“…This may be due to frequent use of hands and fingers to operate the devices. This observation is consistent with previous studies indicating that excessive use of smartphones may adversely affect the median nerve and increase the probability of occurrence of CTS . Other studies found evidence for wrist abnormalities in computer users, such as restricted wrist range of motion and reduced sensory nerve function .…”

“…This observation was consistent with a previous study showing a positive correlation between cumulative hours of computer use and positive Tinel's and Phalen's signs in the right hand . Another study focusing on smartphone use also reported that positive Phalen's and reverse Phalen's test signs were associated with the degree of addiction to smartphones, periods of use, duration of use per day, and duration of continuous usage time . These clinical tests have been used to aid in the diagnosis of CTS, but it should be noted that the reported sensitivity and specificity of Tinel's and Phalen's tests vary from 30% to 100% …”

“…This observation is consistent with previous studies indicating that excessive use of smartphones may adversely affect the median nerve and increase the probability of occurrence of CTS. [7][8][9] Other studies found evidence for wrist abnormalities in computer users, such as restricted wrist range of motion 36 and reduced sensory nerve function. 37 This suggests that intensive users may have a higher risk of developing CTS, and, thus, precautions are required when using electronic devices.…”

“…35 Another study focusing on smartphone use also reported that positive Phalen's and reverse Phalen's test signs were associated with the degree of addiction to smartphones, periods of use, duration of use per day, and duration of continuous usage time. 8 These clinical tests have been used to aid in the diagnosis of CTS, but it should be noted that the reported sensitivity and specificity of Tinel's and Phalen's tests vary from 30% to 100%. 45 Furthermore, the amount of time spent on electronic devices and total number of electronic devices used were positively associated with CSA and FR of the median nerve as well as palmar bowing of the TCL.…”

“…[7][8][9] These studies have attempted to evaluate the effects of smartphone overuse in relation to clinical and functional status of the hand. 7,8 However, individual studies have focused on 1 type of electronic device and have not examined in detail hand-use habits, which may lead to over/underestimation of the findings. Therefore, this study investigates the results of questionnaire, physical, and ultrasound evaluations of the hand in intensive and nonintensive electronic device users.…”