Abstract:
Ever since the devise of internet and handheld gadgets, the world has become a global
village. Among these handheld devices, smartphones have taken the world by storm and their
usage has boomed in the last decade or so. Several studies have reported anatomical changes
(such as enlarged median nerve) and reduced grip strength in the wrist and hand of
smartphone user. Objectives included measurement and comparison of the grip strength and
median nerve cross-sectional area (MN-CSA) between dominant and non-dominant hands of
smartphone users, and, to evaluate, measure and compare the anatomical changes in the fifth
digit of dominant and non-dominant hands of smartphone users. Hundred and twenty-eight
health sciences students were selected aging from 17-25 years. By using the smartphone
addiction scale (SAS), the participants were divided into two groups: low-smartphone users
and high-smartphone users. Details of the smartphone (weight, screen size) were collected
from a reliable smartphone website (GSMArena). Grip strength was measured using a hand
dynamometer. Ultrasound of both hands of each individual was done at the distal crease of
the wrist to evaluate the median nerve cross-sectional area (MN-CSA). X-Ray (finger PA)
was done of both hands. Median value of SAS scores of the 128 participants was 114.5
(>114.5 were classified as high-smartphone users; <114.5 were classified as low-smartphone
users). Results demonstrated that the difference between the MN-CSAs of dominant and non dominant hand of the high-smartphone group was highly significant (p=0.007). The
difference between the MN-CSAs of dominant and non-dominant hand of the low smartphone group was significant too (p=0.0103). The mean grip strength in the dominant
hand of the high-smartphone group was 28.7 kg while in the low-smartphone group it was
29.5 kg. It can be concluded that smartphone over use resulted in an enlarged median nerve,
especially in the dominant hand. It can lead to reduced grip strength of the dominant
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hand in individuals with excessive smartphone use and might also lead to carpal tunnel
syndrome
