When show jumper Lauren Hayes learned the University of Miami’s Acquired Neurosensory Disorder and Treatment Lab was doing research on equestrians and concussions earlier this year, she was quick to sign up. The lab, which has worked with the Department of Defense and the National Football League, was working to gather data on equestrians with and without a history of concussion to determine a normative value, or baseline, for equestrians. With that value, they could better diagnose and treat concussions in equestrians.
A few days before she was scheduled to meet with the team from UMiami, Hayes was in a car accident with her dirt bike. She was airlifted to a nearby hospital, where she was told she didn’t have a concussion or any other major injuries.
Hayes believed she was concussion free the day she met with Dr. Sergio Guerreiro, AuD, an assistant professor of clinical otolaryngology, and Dr. Kayla Minesinger, Ph.D, an entry scientist at UMiami. But later that week she knew something wasn’t right.
“I went to Sergio later that week and just said, ‘I’m not right,’” said Hayes. “I was emotional, I felt really disconnected.”
When Dr. Guerreiro pulled Hayes’ results, he discovered she had suffered quite a severe concussion. Hayes was eligible to participate in a study using Passive Neurosensory Reintegration Training (PNRT), a form of therapy that aims to help the brain relearn how to utilize visual and balance-related signals. In late April, she began treatment, and by the end of her treatment period, Hayes’ symptoms had subsided, and she returned to her normal self.
“My concussion symptoms showed up later, and during the information gathering session, I wasn’t identifying it as a concussion, but they were able to see that’s what it was from the tests, and clearly there was some trauma,” said Hayes.
Why This Research Matters
The idea to gather equestrian-specific data sparked when Will Martin, a Canadian show jumper, came to Dr. Guerreiro after a pair of serious concussions. Martin had been cleared to ride after a fall, but shortly afterwards he’d had another accident when the jump in front of him appeared to be moving. The second fall exacerbated the concussion Martin had already sustained, leaving him unable to ride at all.
Dr. Guerreiro and Dr. Erin Williams, Ph.D., a research assistant professor and co-director of the Acquired Neurosensory Disorder Research and Treatment Laboratory (ANDRTL) at UMiami, treated Martin using PNRT, which is on a multi-axial platform, allowing it to move gently in different orientations: up and down, side to side, back and forth. While on the table, patients are also exposed to different wavelengths of light (similar to red light therapy) and auditory stimulation.
“This table is essentially a bottom-up approach to therapy,” said Dr. Minesinger. “Traditional therapy technically falls under an executive functioning, top-down approach. You’re told to do a task and you perform it. But if you’re concussed, that’s hard to do because your brain is struggling to perform normally. A bottom-up approach means we’re targeting the ‘automatic,’ or subcortical part of the brain — or the part responsible for normal processes you don’t normally think about.”
As equestrians themselves, Dr. Guerreiro and Dr. Williams were inspired by Martin’s results, which led them to begin working on establishing normative values for equestrians. The work is especially important because 42.5% of those suffering from sports-related concussions are equestrians, and over 80% of riders will experience at least one head injury in their lifetime.
Several factors, such as age, biological sex, and pre-existing conditions can impact concussion symptoms, severity, and recovery, and a person’s activities and skillsets can also affect whether the concussion is diagnosed. Physical diagnostic tools evaluate eye movement, balance, visual function, and spatial awareness, and compare an individual’s results against a normative value (or if available, against an individual’s baseline score).
While there are baseline values for non-equestrians and athletes in other sports, the normative value for equestrians could be quite different from the other groups.
“What we’re noticing when we’re performing some of the optometry exams, where we’re basically looking at depth perception and how well the eyes work together at different distances, an equestrian’s ability to perform those eye movements are really impressive,” said Dr. Minesinger. “They’re able to do these really challenging eye movements that you wouldn’t typically see in a normal person within that age group. That’s why it’s important to get baseline normative values for equestrians without head injuries because their normal values are probably different from another athlete.”
They’re also looking to gather data across disciplines because a dressage rider might have different normative values than someone who jumps.
“Someone who only does dressage doesn’t need the same ability to track distances in relation to yourself as someone who is doing cross-country at the advanced level going over massive obstacles at a gallop over uneven terrain,” said Dr. Williams. “Eventers would need higher functioning oculomotor systems compared to someone who’s not doing those sorts of things.”
Because equestrians are showing a higher normative value than a layperson, a concussion could go undiagnosed because though they’re performing lower than their own baseline, it’s still above that of the average person. They could be cleared, just as Hayes and Martin were, but still experience symptoms or be at risk for further injury.
“The doctor could say, ‘Your score is normal, therefore you don’t have a head injury,’ but that’s not necessarily true, because it’s all relative to where they were before the injury,” said Dr. Williams. “Our goal is to get a better understanding, not just for diagnosis, but also to track the effects of therapeutics that come along. More information, in our view, is never a bad thing.”
Next Steps
So far, they’ve gathered data on 30 equestrians, but they’re looking to collect more, and will be doing more evaluations during the Winter Equestrian Festival in Wellington, Fla., this winter.
These sessions include gathering demographics such as age, sex, race, and daily lifestyle habits followed by two concussion questionnaires. The Sport Concussion Assessment (SCAT6) is a subjective survey that ranks symptoms on a scale, and the Convergence Insufficiency Symptom Survey (CISS), which asks participants to rank how difficult close tasks, such as reading, using a computer are. These tools capture a baseline for no concussed individuals and can be utilized to establish normative values for equestrians but also used for comparison purposes for that individual if a concussion is suspected.
Next, participants undergo a neuro-optometry battery, which is comprised of 10 to 12 tests that examine visual acuity (how well your eyes work together to fuse images), depth perception, visual processing, and color field testing (measuring how your peripheral vision responds to different colors of light). The final piece is wearing goggles to diagnose mild traumatic brain injury and concussion.
“The goggles are similar to a virtual reality headset where you’re kind of playing games with your eyes,” said Dr. Minesinger. “Essentially you’re following a dot across a screen in different patterns, and that’s where we capture very refined eye-tracking data that gives us information on the oculomotor vestibular reaction time.”
With enough data, the researchers at UMiami hope to drastically improve concussion diagnosis and recovery for equestrians. Dr. Guerreiro hopes it’ll give organizations like US Equestrian and the FEI a better way to determine whether a rider is safe to get back on a horse after a fall.