The Washington Post on Thursday published a story suggesting that the use of mobile devices is causing young people to sprout horns from their skulls. But a look at the scientific data behind the story finds that such a splashy takeaway is tenuous at best—and atrocious reporting at worst.
The Post’s story was primarily based on a study published back in February 2018 by two Australian researchers. It earned fresh attention last week after being mentioned in a BBC feature on how modern life is supposedly transforming the human skeleton. The study was published in Nature’s open source journal Scientific Reports, which is supposedly peer-reviewed. But the study has significant limitations and flaws, and the Post breezed over them for a sensationalized story.
Perhaps the most striking problems are that the study makes no mention of horns and does not include any data whatsoever on mobile device usage by its participants who, according to the Post, are growing alleged horns. Also troubling is that the study authors don’t report much of the data, and some of the results blatantly conflict with each other.
Last, it appears that the study’s lead author—David Shahar, a chiropractor and biomechanics researcher at the University of the Sunshine Coast in Queensland—has a financial incentive to convince people that their modern lifestyles are deforming their skeletons; Shahar goes by the name Dr. Posture online and has developed devices and techniques to prevent such posture problems. At the time of writing this, the Dr. Posture Thoracic Pillow was currently unavailable on Amazon, though.
All of this didn’t stop the Post from writing an uncritical article with the headline: “Horns are growing on young people’s skulls. Phone use is to blame, research suggests.”
So, let’s bend our heads down to a posture-damaging angle and dig into this study.
First, they aren’t horns
As mentioned, the study doesn’t actually deal with horns. What the Post is referring to in its headline—and what it calls in the article “hornlike spikes”—are actually small bone spurs. And these spurs don’t occur on either side of the skull as horns do, but on the back of the skull at the base.
The bone spurs jut off of what’s called the external occipital protuberance (EOP) of the skull. This is the point at the back of the head where important ligaments that run along the spine attach, as do neck muscles. The EOP can be prominent—if you feel the back of your own head, you may feel a hard lump where the EOP is. It tends to be more noticeable in men, and forensic scientists have used the EOP’s size to determine the gender of damaged corpses and human remains
Like all the places in the body where ligaments and muscles attach to bones, overuse and tensile stress can trigger further bone growth, forming enthesophytes. These are abnormal bony projections, aka bone spurs. In the study, Shahar and his co-author, Mark Sayers, call these EOP bone spurs, enlarged EOPs, or EEOPs.
Whatever they’re called, the most important thing to know about them is that they’re absolutely not important. While their presence may be a subtle hint that a person is straining their neck muscles too much, they are otherwise inconsequential to health; they don’t cause pain or any other symptom. They are unnoticeable unless you specifically look for them in medical images—which doctors tend not to do because, well, there’s really no point.
For these reasons it’s hard to say how common they are, who tends to have them, or if they’re becoming more common in any group. Shahar and Sayers suggest that they are becoming more common in young people. But…
There’s no data to suggest an increased prevalence of these bone spurs
In their study, Shahar and Sayers pulled pre-existing X-ray images from 1,200 chiropractic patients ages 18 to 86 years old (patient ages were fairly evenly distributed through the age groups, and gender distribution was also even among the age groups). They found that around 25% of the people 60 years or older had the bone spurs, which isn’t surprising given that they can develop over a lifetime of muscle use. The younger groups all had lower prevalence—with the notable exception of the 18- to 30-year-old crowd, which had a bone spur prevalence in the range of 40%.
From here, Shahar and Sayers make two large leaps in reasoning: they suggest that these bone spurs are becoming more common and developing in the young and that this trend is due to the neck stress of looking down at handheld gadgets.
Taking on the first leap: a convenience sample of chiropractic patients is not necessarily representative of the population overall. There’s no basis to make the argument that the 300 18- to 30-year-olds in the study accurately represent that age group and can inform us about overall trends. There was obviously a reason why this relatively young group checked into a chiropractic clinic in the first place. Perhaps those who do are simply more likely to have these bone spurs for whatever reason. And because we don’t have data from chiropractic patients at different time points, we can’t say if anything is changing in this self-selecting group of young chiropractic patients either.
Moreover, the authors were unclear on how and why they selected the X-rays they used for the study. They say that they excluded chiropractic patients who reported “greater than mild” pain but don’t explain why. They also say that some of the patients reported no pain. Yet they had neck X-rays for those patients.
“That’s a little bit odd,” Dr. Todd Lanman told Ars. Lanman is a spinal neurosurgeon and clinical professor at the University of California, Los Angeles. He cautiously added that he’s unfamiliar with the common practices of chiropractic clinics in Australia but noted that he wasn’t sure why they would have taken such images in the apparent absence of a clinical reason.
Ars reached out to Shahar for an interview and specifically asked about this in an email. Shahar responded but declined to explain and only offered to discuss the matter “in the near future.” He wrote that he is currently “overwhelmed by the media’s attention” and referred me back to the study’s skimpy methods section.
The weak connection to mobile devices
For their second leap, Shahar and Sayers note that many young people today use smartphones and tablets, and recent studies have suggested that when people look at their devices, they bend their necks at angles that add more weight to the spine. Hypothetically, this can create stress that could spur bone growth and other problems.
Indeed, Lanman and his colleagues have anecdotally reported seeing an increase in young patients complaining of neck and upper back pain. He has also seen them displaying damaging postures while fixating on their phones. This has led to the hypothesis of such a thing as “text neck.”
In a 2017 article in The Spine Journal, Lanman and colleague Dr. Jason M. Cuéllar note that recent research on the effects of neck postures on the spine estimated that “while in a neutral position the head weighs a relative 10-12lbs, compared to 27lbs at 15 degrees, 40lbs at 30 degrees, 49lbs at 45 degrees and 60lbs at 60 degrees.” But Lanman and Cuéllar were cautious in their conclusions, noting that “clinical studies will be needed to evaluate” concerns linked to this seemingly new source of neck stress.
Shahar and Sayers’ study isn’t one that’s going to provide any answers, however. As Lanman pointed out, the researchers could have simply gone back to their patients and tried to collect data on phone and tablet usage to try to find a correlation, but they didn’t. While it’s plausible that gadget use could play a role in the patients’ bone spurs—and perhaps whatever prompted them to go to a chiropractor in the first place—the study can in no way make the case without usage data.
The study is thin on data overall and has a blatant flaw
While Shahar and Sayers’ study doesn’t include the usage data that would have made for a conclusion, the data that it does include is barely represented in the publication. The study has just two figures—and one of them conflicts with the results.
In the text of the publication, Shahar and Sayers write that “Logistic regression analysis indicated the presence of an EEOP to be significantly predicted (72.3%; P < 0.001) using the following variables: sex, the degree of forward head protraction (FHP), and age. Sex was the primary predictor with males being 5.48 times more likely to have EEOP than females (P < 0.001)” (emphasis added).
Yet, the researchers’ data figure on the prevalence of an EEOP broken down by sex and age completely conflicts with the five-fold change they report from the regression analysis.
Ars specifically asked Shahar about this, but he again declined to respond to the question.
Lanman concludes that the study should be interpreted cautiously and that the authors should explain their data better. Moreover, he doesn’t think anybody should be worried about bone spurs on the back of their skull. “The spur itself is not likely to ever be symptomatic.”
That said, he recommends people with neck and upper back pain to “be mindful of your posture.” He recommends holding your phone higher to keep from bending your neck too much and adds that texting with two thumbs is better than one.
Good posture, he emphasizes, involves having the “ear canal directly above shoulders directly above hips.” It may feel uncomfortable at first, but after a while, you’ll go, “wow, that feels so good,” he says. Last, he recommends that his patients do neck and back stretches in the morning and night in bed with their heads tilted back (sometimes with a towel between the shoulder blades).