Extensive smartphone use is contributing to young adults growing horn-like structures on the back of their heads, a new study has found.

The horn-like growths on human skulls were considered to be a rare occurrence when they were first discovered in the 1800s, but Australian researchers now say the bizarre condition is becoming common in young people.

The bony spikes were typically associated with hunched-over aging people, following years of poor posture, but now the condition is present in almost half of the 18-30 year-olds studied.

View photos Smartphone use is being blamed for poor posture in young people, contributing to horn-like growth on back of their heads. Source: Getty, file. More

Dr David Shahar and Associate Professor Mark Sayers at The University of the Sunshine Coast found 40 per cent of those studied had developed the “bony outgrowths” on the back of their skulls, as a result of “forward head protraction”.

The scientists believe the 10–31 mm growths are a result of prolonged use of hand-held gadgets, with people spending too much time looking down at smartphones and tablets.

View photos A horned spike of almost 28mm was found on the back of a 28-year-old's skull, as a result of “forward head protraction” linked to use of hand-held devices. Source: Scientific Reports More

The spike-like growth, scientifically known as the “external occipital protuberance” is found at the lower back of the skull, just above the neck, Dr Shahar told BBC.

As we hunch over hand-hold gadgets, we crane our necks to hold our heads forward in an unnatural position, to support the weight of about 4.5kg, he explained.

View photos A similar growth, of 24.5mm, is seen on the back of the skull of a 58-year-old. The condition is typically associated in ageing humans, from years of long-term poor posture. Source: Scientific Reports More

The researchers say the growths are so prominent that anyone with the phenomenon may be able to feel the bony lump on the back of their head with their fingers.

Extended smartphone use has also been blamed for causing permanent damage to the eyesight of a two-year-old girl.

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