The Concussion Nobody Diagnosed
The SparkNotes
Somewhere between half and four fifths of concussions are never reported or never recognized.
The most common reason athletes give for not reporting is not wanting to be pulled from future games.
A third of athletes in one study had symptoms of a concussion nobody ever labeled as one.
The physical therapy guideline says time since injury should not be the primary determinant of whether assessment is appropriate.
Being evaluated for an undiagnosed concussion is a Grade A recommendation — its strongest evidence tier.
The Whole Story
Think back to a time you got your bell rung.
Maybe you saw stars for a second. Maybe you finished the game feeling strange and put it down to being tired. Maybe you told nobody, because telling somebody meant coming off.
That event probably never appeared in any medical record. And a surprising amount of the current thinking about concussion is aimed at exactly that.
The size of the gap
Between 50 and 80% of concussions are thought to go unreported or unrecognized.
One study of 335 collegiate athletes, surveyed at the end of their playing careers, put numbers on both halves of that. Around a third had reported a concussion. Another 11% said they had suffered one and deliberately not told anyone. And a further third described symptoms consistent with a concussion — seeing stars, losing consciousness, losing memory — that had never been diagnosed as one.
Add those together and nearly half of them had experienced at least one concussion. Most of those were never on a chart.
Why athletes do not say anything
The same study asked the ones who knowingly did not report why. Their answers are worth reading slowly, because none of them is stupid:
They did not want to be removed from future games — the most common answer, given by around two thirds.
They did not want to be removed from the game they were in.
They did not want to let their teammates down — half of them.
They did not think the injury was serious.
And more than a third did not know it was a concussion.
That last one is the important one. You cannot report what you do not recognize, and "seeing stars" does not sound like a brain injury to a nineteen-year-old.
What makes someone finally say it
In my experience it is usually one of two things. They start noticing memory problems — not being able to remember a play, or what just happened. Or the symptoms get worse: a headache, or nausea, that will not settle.
There is also a timing problem that catches people out. Symptoms do not always arrive immediately. Sometimes there is a delay in their onset, so an athlete seems fine — and genuinely feels fine — and the symptoms show up afterwards.
Why this is not just history
Here is the part that changes what you might do about it.
The physical therapy clinical practice guideline for concussion states that time since injury should not be the primary determinant of whether physical therapy is appropriate. The guideline applies whether the concussive event was recent or in the more distant past.
It goes further. Evaluating for the signs and symptoms of an undiagnosed concussion, in people who have had a concussive event but were never diagnosed, is one of its Grade A recommendations — the strongest tier it uses.
So an assessment years later is not a courtesy. It is the guideline.
What would actually get looked at
Not a scan. A concussion assessment in physical therapy is an examination of four systems, worked through in an order set by whatever is most irritable.
THE NECK. Neck pain, headache, dizziness and difficulty focusing on something can all come from the cervical spine rather than from the brain. The neck gets triaged first for exactly that reason.
THE VESTIBULAR AND OCULOMOTOR SYSTEM. Balance, eye movement, gaze stability, and how you cope in visually busy places — a supermarket aisle, a crowd.
AUTONOMIC FUNCTION AND EXERTIONAL TOLERANCE. Heart rate and blood pressure lying, sitting and standing, and a graded exertion test to find where your system actually stops coping.
MOTOR FUNCTION. Static and dynamic balance, coordination, and dual tasking — doing a movement and a thinking task at the same time, which is what sport and driving and stairs actually are.
Several of those can be measurably off in someone who feels basically fine, and who has told themselves for years that this is just how they are now.
The honest limits
Two things this article is not saying.
It is not saying every old head knock needs an assessment. Most concussions resolve, most people recover relatively quickly, and the guideline is emphatic that patients should be told so — because expecting a bad recovery makes one more likely.
And it is not saying an assessment will explain everything. Symptoms attributed to concussion are non-specific. Headaches, dizziness, fogginess, poor sleep and low mood are all reported by people who have never been near a concussion, and they have many other causes. A good assessment is partly a process of working out which of those is in play.
What it is saying is narrower and firmer: if you had a concussive event and something has not been right since, the file is not closed, and time is not the reason to leave it.
That assessment is a physical therapy assessment, and it is one this practice does.
Follow along as Resurgo comes together.
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