The First 48 Hours After a Head Knock
The SparkNotes
If a concussion is suspected, the athlete comes off. Suspicion is enough — you do not need certainty.
They do not go back in that day unless an experienced healthcare professional has assessed them properly, and that assessment takes 10 to 15 minutes in a quiet place.
Symptoms can appear minutes, hours or days later. A normal-looking athlete at the final whistle is not an all-clear.
Strict rest is out. Relative rest for about two days, then light activity as tolerated.
Any deterioration is an emergency, not a wait-and-see.
The Whole Story
Your kid takes a knock. They get up. They look at you and say they are fine.
What you do in the next two days matters more than almost anything that happens after.
On the field: suspicion is the threshold, not certainty
The international consensus is blunt about this. If there is suspicion of a possible concussion, the player comes off — to avoid further injury while it is being worked out.
You do not need to be sure. Suspicion is the bar, and it is deliberately set low.
Certain signs mean immediate removal, no discussion: loss of consciousness or suspected loss of consciousness, a seizure, tonic posturing, unsteadiness or poor balance, confusion, behavior that is not like them, and any gap in their memory of what happened.
And the part parents most often get wrong — an athlete showing those signs does not go back in that day. The only exception is a proper assessment by an experienced healthcare professional, on the spot, that finds another explanation. Rolling an ankle badly enough to be off balance is a different thing from being concussed, and telling those apart is the assessment's job.
What actually gets asked in the first ten minutes
Standing on a sideline, the questions arrive in more or less this order. Can they go back in? When will they be better? Are you sure it’s a concussion? Does my son or daughter need to go to the emergency room? Do I need to wake them up every thirty minutes tonight?
They are the right questions to ask. Most of what follows is the answer to them.
Ten to fifteen minutes, somewhere quiet
A proper sideline screen is not a question asked at the touchline while play continues.
The consensus says a multimodal screen takes at least 10 to 15 minutes, and that sport organizations should allow for that — preferably in a quiet area, away from the noise and the pressure of the match.
It also says something worth quoting to anyone who tells you a quick check was enough: any screening assessment short of a full multimodal evaluation may be inadequate to allow continued participation.
Symptoms arrive late, and that catches people out
This is the single most misunderstood thing about concussion.
Signs and symptoms may present immediately, or evolve over minutes, hours or days. An athlete who seems completely normal when they come off the pitch can look very different at bedtime.
So the assessment is not one moment. They should be checked again over the following hours and days, and someone should be keeping an eye out that evening.
The instruction that changed: rest
Most of us were taught to put a concussed kid in a dark room and wait until every symptom was gone.
That advice is now explicitly against the evidence. The consensus states that recommending strict rest until symptoms fully resolve is not beneficial.
What is recommended instead:
RELATIVE REST for about the first two days — normal daily activities, and reduced screen time. Not a blacked-out bedroom.
LIGHT ACTIVITY straight away, in the first 24 to 48 hours, as long as it does not more than mildly worsen symptoms. Walking counts.
AFTER 24 TO 48 HOURS, a return to physical activity as tolerated — walking, stationary cycling — while strictly avoiding anything with a risk of contact, collision or a fall.
Reduced screen use in the first 48 hours is worth doing. Beyond that, the evidence that it helps runs out.
And a detail that saves a lot of unnecessary panic: mild symptoms coming on during activity are expected. If the flare is mild and short — under an hour — it does not delay recovery. Stop if it is more than that, and resume when they are back to where they were.
The one to watch that night
Sleep disturbance in the ten days after a concussion is associated with a higher risk of symptoms that persist. If they are not sleeping, that is worth reporting rather than waiting out.
So the honest version is: most concussions settle, and the minority that do not have a route.
That is not reassurance for its own sake. The physical therapy clinical practice guideline makes telling you so a Grade A recommendation — its strongest evidence level — specifically because expecting a bad recovery makes a bad recovery more likely. Being told "this could take months" when it probably will not is itself a risk factor.
Most people recover from a concussion relatively quickly.
The thing most people are not told
When it is not a wait-and-see
Everything above assumes a stable athlete who is being monitored. Deterioration is different.
Worsening confusion, a seizure, repeated vomiting, weakness or numbness, or any decline in how they are responding is an emergency. That is an ambulance or an emergency department, not a phone call in the morning.
What happens next
Most concussions settle. When they do not, there is a clear next step rather than a shrug.
If dizziness, neck pain or headaches are still there after ten days, the consensus recommends cervicovestibular rehabilitation — treatment aimed at the neck and the balance system rather than at waiting. Symptoms lasting more than four weeks are defined as persisting, and warrant a full assessment rather than more time.
Both of those are physical therapy territory, and they are things this practice does.
Follow along as Resurgo comes together.
SECOND SOURCE: Quatman-Yates CC, Hunter-Giordano A, Shimamura KK, Landel R, Alsalaheen BA, Hanke TA, McCulloch KL. Physical Therapy Evaluation and Treatment After Concussion/Mild Traumatic Brain Injury: Clinical Practice Guidelines Linked to the International Classification of Functioning, Disability and Health From the Academy of Orthopaedic Physical Therapy of the American Physical Therapy Association. Journal of Orthopaedic & Sports Physical Therapy. 2020;50(4):CPG1–CPG73. doi:10.2519/jospt.2020.0301
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