The effect of smartphone addiction on hand joints in psoriatic patients: an ultrasound-based study

Background: Distal interphalangeal (DIP) arthritis is a frequent form of psoriatic arthritis being often linked to nail psoriasis. Modern society is characterized by overuse of smartphones. Indeed, literature has recently focalized on research into smartphone addiction and health-related problems. Objectives: As smartphone addiction is able to determine overuse and repeated movements of DIP joints and nails, the aim of this study was to evaluate the impact of smartphone use on hand joints of young psoriatic patients. Methods: An observational study involving four different groups such as non-smartphone-addicted (SA) psoriatic patients, SA psoriatic patients, non-SA controls and SA controls was performed. Each subject underwent an ultrasound examination of both hands by three independent and blinded to group assignment radiologists. A specific score was used to evaluate the inflammatory state of the analysed joints. Results: The total ultrasound score was statistically significantly higher in SA controls respect to non-SA controls (3.4 vs. 1.4; P < 0.05) as well as in SA psoriasis patients compared to non-SA psoriatic subjects (15.2 vs. 6.7; P < 0.01). Higher mean of ultrasound score was found for left hand in controls (both SA or not) and for right hand in psoriatic subjects (both SA or not), however without reaching statistical significance. Conclusions: Smartphone overuse was found to be linked with higher signs of inflammation of musculoskeletal structures of hands joints in both psoriasis and controls through ultrasound examination. Therefore, smartphone overuse may be a factor which facilitate or speed up the possible development of psoriatic arthritis.