In edition 257 of BC Disease News (here), we reported that an orthopaedic surgeon in San Francisco was diagnosing a form of carpal tunnel syndrome (CTS) in increasing numbers of patients who had exhibited nerve inflammation (or ‘median nerve neuritis’), numbness, tingling and sharp pains in their hands, wrists and arms.
He noticed that many of his patients were frequent ‘selfie’ takers and, on the basis that capturing a photo of yourself with a front-facing smartphone camera requires hyperflexion of the wrist inwards, he associated the act of persistent ‘selfie’ taking with symptoms observed. As a result, he dubbed the condition ‘selfie wrist’.
It would seem, however, that novel disorders arising in the modern digital age are not restricted to ‘selfie wrist’.
An article written in The Sun, this week, reported on an ‘epidemic’ of patients with so-called, ‘iPhone hands’, or ‘iPhone tendonitis’. Those suffering with this newfangled condition will typically complain of repetitive strain injury which triggers pain and inflammation at the base of the thumb.
Scientific evidence, in support of this assertion, was published in the Reumatismo journal, in April 2019.
Researchers at the University of Malaga, in cooperation with Italian (Fondazione Don Carlo Gnocchi) and American (Gannon University) groups, discovered a ‘direct correlation between people's occupation and the cause of thumb pain’.
Lead Author and Physical Therapist, Professor Rachel Cantero, claims that ‘atrophied thumbs are [becoming] more and more frequent in ... practice’. She attributes tissue wastage to repeated thumb use for texting on smartphones:
‘Adults using mobile phones punch out numbers with their thumbs and develop synovitis in their carpometacarpal joint’.
Irritation of the carpometacarpal joint, which is instigated by thumb-swiping, may be diagnosed as De Quervain’s tenosynovitis, whereby the sheath (synovium), surrounding tendons at the base of the thumb, becomes inflamed.
Physio, Dan Baumstark, considers that persistent swiping to unlock screens and participate in mobile apps, may increase the risk of thumb injury, especially in younger individuals:
‘This motion may at first appear to be quite harmless, but repetitive motion can have serious long-term effects if performed dozens or even hundreds of times daily.
Several tendons of the thumb pass through a compartment in the wrist that serves to keep the tendons in place as they are used’.
The University of Malaga researchers even go as far as to allege that increasing mobile phone use may result in humans evolving a ‘pinch-like grip with our hands’, thereby leading to a reduction in brain function.
However, there is little evidence to support this theory, other than studies which have established that disorders, like arthritis, are associated with impaired brain activity, sometimes referred to as ‘brain fog’.
In other news, Bob Chatterjee, a surgeon at Harley Street Spine and Highgate Private Hospital, has warned that prolonged flexion of the neck, in order to allow smartphone users look down at their mobile phones for long periods of time, has caused a spike in the number of patients complaining of so-called ‘text neck’. Affected individuals commonly experience migraines and blurred vision.
We discussed, in edition 276 (here), that the UK Government had launched the Immersive and Addictive Technologies Inquiry, which is investigating ‘how the addictive nature of some technologies can affect users’ engagement with gaming and social media, particularly amongst younger people’.
While injuries caused by mobile phones may be self-inflicted, if devices are deliberately designed to encourage protracted use, potentially leading to addiction, it could be argued in future that, but for technological advancement, user exposure periods would have been shorter and repetitive strain injuries would be less prevalent – an insight into a developer’s conceivable duty of care.
 Villafañe JH et al., The hominid thumb and its influence on the employment during evolution. Reumatismo. 2019 Apr 1;71(1):51-52. doi: 10.4081/reumatismo.2019.1138. <https://www.researchgate.net/publication/332182417_The_hominid_thumb_and_its_influence_on_the_employment_during_evolution> accessed 19 June 2019.
 ‘De Quervain’s tenosynovitis – inflammation of the tendons of the thumb’ (November 2017 Oxford University Hospitals NHS Trust) <https://www.ouh.nhs.uk/patient-guide/leaflets/files/11303Pdequervains.pdf> accessed 19 June 2019.
 Shin SY et al., Cognitive Impairment in Persons With Rheumatoid Arthritis. Arthritis Care Res (Hoboken). 2012 August ; 64(8): 1144–1150. <https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3744877/pdf/nihms-504018.pdf> accessed 20 June 2019.
Schrepf A et al., A multi-modal MRI study of the central response to inflammation in rheumatoid arthritis. Nature Communications , vol. 9 , 2243 , pp. 1-11. <https://www.nature.com/articles/s41467-018-04648-0.pdf> accessed 20 June 2019.