Shaun Best / Reuters

Long after the pitch was thrown, after the screens dimmed and the books snapped shut, I reached the most despairing days of my concussion. The beginning had been fairly easy—as easy, that is, as getting concussed can ever be. The initial diagnosis was optimistic, symptoms were consistent with mild traumatic brain injury, and I assured my friends and family I’d be back to normal in a matter of weeks, if not days.

After all, the knock was nothing terrible: a low 80s heater to the dome from a D3 freshman. I was wearing a helmet. It was a sunny California afternoon. We all thought I’d be fine. I went to my evening politics seminar after practice and don’t remember feeling hazy or otherwise out of sorts. But the next day I started experiencing symptoms. And then, my symptoms started getting worse.

I soon learned that my confidence had been misplaced, and that despite the recent cultural shift toward focusing on brain injuries among professional athletes, modern medicine still has a long way to go before concussions are truly understood. It was this lack of understanding that was, for me, much more frustrating than the felt reality of my injury. The Centers for Disease Control estimates 1.7 million people in the United States suffer some form of traumatic brain injury every year—more than double the number of heart attacks that strike Americans each year. About 75 percent of those brain injuries are considered concussions or other forms of mild injury. And 80 to 90 percent of people will recover from a concussion within a seven to 10 day period, according to the National Institutes of Health. The other 10 to 20 percent are people like me, languidly drifting toward recovery at a more uncertain pace—like an amoeba in a petri dish.

All this highlights one of the great paradoxes of modern medicine: Some of the most common ailments remain some of the least understood.

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Due to a host of reasons, doctors and medical professionals still struggle to answer seemingly basic questions about concussions. “For the vast majority of concussions that are treated in the E.R. and in the trainer’s room, there is currently no prognostic test available,” said Robert Siman, a researcher and professor of neurosurgery at the University of Pennsylvania.

This is partly because the very diagnosis and monitoring of a concussion are based on an amalgam of imperfect tests, none of which fully examines the underlying pathophysiological nature of the injury. New research assessing the severity of concussions through blood testing may eventually help unlock new methods for understanding such injuries, but further trial is still required. For now, when a person is suspected of having sustained a mild traumatic brain injury, they undergo a series of cognitive and symptom-based assessments. How is your memory? Are you experiencing headaches? Nausea? Dizziness? Loss or lack of balance? Sensitivity to light or sound? Patients are often asked to fill out a scorecard ranking the severity of their symptoms, and as symptoms vanish, they return to normal activity.

“We always look at mind, body, and spirit,” said R. Robert Franks, an osteopathic family physician and spokesperson for the American Osteopathic Association. “It’s an all-encompassing pathology, and you have to look at the complete patient with this, you have to look balance, you have to look vision, you have to look cognition, you have to look at neck pain for whiplash type injury, you have to look at anxiety, depression … you have to look at sleep. We focus so much on headache and dizziness, and those other symptoms kind of go by the wayside, but the athlete is not ready to go until we have all of those in check.”

In more serious cases of brain injury, imaging from a C.T. scan or an M.R.I. can reveal specifics, like an intracranial bleed, which takes longer to heal. But in the majority of patients suffering from concussions, it can be difficult if not impossible to say whether they will be part of the 80 to 90 percent that recovers quickly, or the latter 10 to 20 percent that needs more time. For the most part, doctors end up cobbling together an understanding of a person’s injury through subjective reports, brain imaging, and other tests. “So you can see a number of different things,” said Alison Cernich, the director of the National Center for Medical Rehabilitation Research at the NIH, “not just through cognitive testing and not just through asking the person, but by looking at some of the other symptoms.”

Symptom-scoring became the primary means for doctors to assess me as the weeks of my concussion wandered on. Every other day I filled out a questionnaire ranking my various ailments on a scale of 1 to 6. This process proved problematic: What is a 4, really? Individuals have different pain thresholds and rankings; and those individual rankings are easily subject to shift. At the beginning of my concussion I recall putting down 1s and 2s. But as the days wore on I realized I had been swayed by my own optimism. Now I really was a 2, back then I should have been a 4! I would suddenly realize that I felt better, but I didn’t have the numeric wherewithal to express my progress because I had skewed my initial ranking. Not only is such a scale nebulous and subjective, it relies on the perception of someone with a head injury. Even today, fully healed, a 1-to-6 scale would prove difficult for me to navigate. But imagine trying to fill out the scorecard while concussed. Imagine, while brain-addled, trying to give doctors, or anyone for that matter, a clear picture of your mind and body. And then imagine that picture serving an important role in your overall diagnosis.

I don’t want to give the impression that I was monitored solely on self-reported symptoms. Doctors regularly checked my eyes and memory. I had a C.T. scan taken, which came back clean. Doctors often asked me to perform balance, dexterity, and mobility tests, and they monitored my vitals and reflexes. I rode a stationary bike to see if activity exacerbated my symptoms. But I was not treated the same way a professional athlete might be treated. Which meant I wasn’t seen by specialists like Franks, who is also the director of the Rothman Concussion Institute and the co-medical director of the Jefferson Comprehensive Concussion Center. Franks is the team physician for U.S. Wrestling and consults for the Philadelphia Phillies, as well.

“Right now I think the biggest help for us with concussion is that we now have objective and subjective signs,” said Franks. “And you know, when I first started this it really was all about what the patient told us.” According to Franks, the measurement of balance is a direct reflection of certain elements of brain function. Advances in computer-based neuropsychological testing—a process that compares pre- and post-impact scores to assess cognitive ability—help, too. “We can also now objectively look at cognition, the way the brain is working,” he said.  

But a passage from The Consensus Statement on Concussion in Sport, a document that doctors and trainers rely on to treat concussions, says that while neuropsychological tests can offer “important data” for clinicians to consider, they “should not solely be used to diagnose concussion.” The guidelines also caution against widespread adoption of such tests, citing “insufficient evidence” for such a recommendation.

The problem is that we can’t see all of the inner-workings of the brain. As the neurosurgeon Siman told me, “concussion produces a sort of wide array of non-specific symptoms, non-specific in the sense that none of them are specific to concussion.” Just because a patient is experiencing headaches, mood swings, and trouble sleeping, doesn’t mean the patient is concussed. And just because a person is reporting symptoms, doesn’t mean those symptoms are accurate. Athletes, especially those competing for their paycheck, have all sorts of incentives to underreport symptoms to get back on the field. Similar pressure to misreport applies to students afraid of falling behind in class (or afraid of taking finals), as well as individuals whose jobs could be in jeopardy. “Our other big challenge continues to be those who don’t report symptoms to us,” Franks said.

All of this is to say that doctors depend a great deal on symptom analysis and some of those symptoms require subjective reporting. This causes frustration from the perspective of scientific rigor, a frustration that has led many researchers, like Siman, to look for alternative means of evaluation. Siman’s work has largely involved tracking a protein fragment, SNTF, in the bloodstream. He recently completed a study using blood samples from Swedish professional ice hockey players, where he found that the existence of elevated levels of SNTF in the blood correlated with the players’ recoveries from concussions. This type of study, and others like it that track certain biomarkers, could potentially change the foundation of how we understand concussions. “SNTF is something whose production is actually tied to the underlying pathophysiology that causes problems after a concussions” said Siman. In other words, the presence of this protein fragment could help show how severe a person’s injuries are.

Siman likes to refer to his research as an effort to find the “Troponin blood test for brain damage.” If someone is suspected of having had a heart attack, one of the most important diagnostic measures is to test for the protein Troponin in the blood. Troponin, usually only found in cardiac muscle cells, spills into the blood when those cells die. “A finding of an elevated level of Troponin in the blood is one of the key diagnostics routinely used for the diagnosis of heart attack.” said Siman. “So we’ve been looking for a brain injury counterpart to that.” Just as doctors track Troponin to diagnose a heart attack, Siman hopes a different protein can be found and tracked as a reliable diagnostic for concussions.

Other researchers are laboring to find similar objective, pathophysiological indicators of concussions. In addition to biomarkers in the blood, researchers have been experimenting with alternative imaging techniques. But for now, neither approach is recommended outside of research settings, according to The Consensus Statement on Concussion in Sport. Several doctors told me that developing biomarkers for assessing patients with concussions could be an important step forward—especially among those who are reluctant to acknowledge they’re still suffering from injury.

“[We] have a hard time often convincing parents, coaches, athletes, that yes, you’re still seeing residual concussion symptoms here,” Franks said. But the existence of a reliable biomarker could change the nature of that conversation. It would provide damning evidence that a player is still concussed. “I think that [a biomarker] is going to be the wave of the future, we just don’t have one that we’re 100 percent, you know, ready for yet,” he said.

Until then, doctors continue to rely on what Siman calls, “indirect measures of brain function,” to determine the extent and severity of a concussion. And for those of us without special assistance from professional athletic trainers, that makes the lousy experience of a concussion all the more muddled. This is without even going into what we still don’t know about treating concussions, an area sometimes no more mature than our ability to diagnose.

In the weeks after I thought I healed, I labored through headaches that Advil only dulled, but never took away. I was unsure whether my discomfort came from some lingering cognitive dissonance, or perhaps whiplash, as one doctor suggested may be the case. I recalled bygone scorecards of my days stranded in a sea of 1s and 2s, and wondered: Am I better now? Was I still concussed then? I flinched involuntarily when a door slammed shut, or when a shard of sunlight caught me from from behind the blinds. Often I retreated to my room—construction paper muffling the windows—and lay on my back, spinning a baseball into the air and lulling myself with the rhythmic smack of tightened leather on my palm. It was all I could do to keep my mind off the uncertainty of a lengthening recovery.

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