Humans appear to be growing horn-like protrusions at the back of the head, and researchers believe smartphones and tablets may be to blame.

Two Australian academics have been studying the phenomenon for several years. Their research lays out a compelling case for the use of handheld electronics leading to a noticeable change in the skeletons of young adults.

David Shahar and Mark Sayers began looking at the issue when Shahar – a practising chiropractor who calls himself “Dr. Posture” – noticed that X-ray results of many of his younger patients showed unusual bulges protruding from the back of the skull, just above the neck.

Looking at more than 200 people between the ages of 18 and 30, Shahar and Sayers found that 41 per cent of them had horn-shaped bone spurs in the backs of their skulls. All of the protrusions measured at least one centimetre while the largest was approximately 3.5 centimetres long.

Up until the early part of this decade, it was largely assumed that it was much more rare for these protrusions to be seen in young people. Medical evidence suggested that they were more common in older people, who had spent several decades developing them due to long-term pressures on their spine.

Further research showed that assumption to be false. As revealed in a 2018 paper by Shahar and Sayers, people aged 18 to 30 were much more likely to have the protrusions than people in their 30s, 40s or 50s. Only once people entered their 60s did the level of protrusions even start to approach the level seen in the youngest adults.

The significant age gap allowed researchers to rule out activities such as sleeping position and bicycle posture, and focus instead on newer trends.

“We hypothesize [the protrusions] may be linked to sustained aberrant postures associated with the emergence and extensive use of hand-held contemporary technologies, such as smartphones and tablets,” the researchers wrote.

“Our findings raise a concern about the future musculoskeletal health of the young adult population and reinforce the need for prevention intervention through posture improvement education.”

Shahar and Sayers believe the increase in handheld device use is putting unprecedented strain on users’ bodies. As people tilt their heads forward to look at their screens, the researchers hypothesize, they increase the weight load on the muscles located at the back of the head, causing bone to grow to help the body cope. Better posture could help people avert this sensation, they said.

Men are more likely to have the protrusions than women. The researchers suspect this is because men are more likely to use their devices for gaming or watching sports events, requiring longer periods of holding the devices, while women are more likely to use them for shorter social activities.

“Although the ‘tablet revolution’ is fully and effectively entrenched in our daily activities, we must be reminded that these devices are only a decade old and it may be that related symptomatic disorders are only now emerging,” they wrote.