Mild traumatic brain injury (concussion)

What is a concussion, and is it the same as a mild traumatic brain injury?

Yes. The terms are used interchangeably. The US Centers for Disease Control and Prevention defines a concussion as a type of traumatic brain injury caused by a bump, blow, or jolt to the head, or by a hit to the body that causes the head and brain to move rapidly back and forth. That sudden movement can make the brain bounce or twist inside the skull, producing chemical changes and sometimes stretching and damaging brain cells.

'Mild' is a grading of the initial injury, meaning there was no prolonged loss of consciousness and no structural damage visible on imaging. It says nothing about how long symptoms will last or how disruptive they will be. A concussion that keeps someone off work for three months is still a mild TBI.

What are the symptoms of a mild traumatic brain injury?

Concussion symptoms cluster into four groups. Most people have some from more than one group, and the mix can change over the first days.

Symptoms are usually worst in the first one to two days and then settle. The thing worth tracking is the symptom threshold, meaning how much physical or mental effort you can manage before symptoms climb. Early on it may be a few minutes of screen time, and recovery shows up as that number creeping up week by week.

When is a head injury an emergency?

Most concussions do not need emergency treatment, but some head injuries do. Go to an emergency department, or call emergency services, if any of the following appear after a head injury:

• A headache that gets progressively worse and does not go away
• Repeated vomiting, or new nausea and vomiting hours after the injury
• Increasing drowsiness, difficulty waking, or loss of consciousness
• Weakness, numbness, or loss of coordination in the arms or legs
• Slurred speech, confusion, agitation, or behavior that is out of character
• One pupil larger than the other, or new problems with vision
• Seizures or convulsions
• Clear fluid or blood from the nose or ears
• Any head injury in someone taking blood thinners

Even without these signs, anyone who has had a head injury should be assessed by a clinician before returning to driving, safety-sensitive work, or sport. This page is educational and cannot replace that assessment.

Why do concussions at work need their own plan?

Nobody has a precise count of US concussions, because many are never seen by a doctor. The CDC's estimate for sports and recreation alone is 1.6 to 3.8 million a year, and that leaves out falls at home, car crashes, and injuries on the job. At work, the usual causes are slips, trips and falls, being hit on the head by falling packages or equipment, and vehicle crashes while driving for work.

That puts package handlers, delivery drivers, warehouse staff, and manual laborers at the front of the line. Their jobs mix lifting, noise, visual clutter, and often driving, and those same things are what tend to bring symptoms back when someone returns. Our work accommodations guide covers how to plan around them.

How long does concussion recovery take?

There is no single average concussion recovery time, but the shape is consistent. For most adults, symptoms settle within days to a few weeks, and the median return to work is one to two weeks. A minority still have symptoms after a month, which is sometimes called persistent post-concussion symptoms or, in older terms, post-concussion syndrome. Roughly 1 in 5 adults is still off work six months after the injury. How large that group is depends on the study and the definition.

Research has found a handful of factors linked to a faster or slower course. They describe groups of people, so none of them can tell you how your own recovery will go.

Look at the right-hand column. Early pain, a neck injury, and a history of anxiety or depression have little to do with the brain injury itself. They raise the nervous system's general alarm level. That is why persistent headache and neck pain after a concussion often behave like other chronic pain problems, where the tissue has healed and the system stays sensitized. Our page on central sensitization explains how that happens.

How is a mild concussion treated?

Mild concussion treatment has moved away from long stretches of complete rest. Current guidelines, including the Ontario Neurotrauma Foundation's, recommend relative rest for the first 24 to 48 hours, then a gradual return to activity kept below the level that brings symptoms on.

1. Initial triage. Rule out the red flags above; assess other injuries, particularly to the neck.
2. Early education. Plain information about what a concussion is, how recovery usually goes, and how to pace activity. Education on its own is linked to better outcomes.
3. Relative rest, then graded activity. Light aerobic activity that does not raise symptoms is encouraged early; screen time and sustained concentration are limited initially and expanded stepwise.
4. Targeted therapy where needed: vestibular rehabilitation for dizziness, treatment of the neck for cervicogenic headache, sleep and mood support.
5. Return-to-work planning with the employer, built around the person's symptom threshold and essential job demands. See return to work after concussion.

When pain is what lingers, whether ongoing headache, neck pain, or a general sensitivity to activity, it often overlaps with the fear-avoidance pattern on our kinesiophobia page. Someone who has learned that activity hurts starts avoiding it, loses fitness, and gets more sensitive. Brain-retraining approaches for chronic pain target that loop, and how it works describes ours.

Should you stay off work after a concussion?

Usually not for long. A 2014 review by the International Collaboration on Mild Traumatic Brain Injury Prognosis found that most workers are back within three to six months. The research it drew on links staying at work, or returning early, to better health, well-being, social connection, and quality of life, and to fewer medical visits. People who cannot return report more physical complaints, and more anxiety, depression, and isolation.

So the aim is to avoid medically unnecessary delay. Change the work instead of removing it, with fewer hours, lighter mental load, a quieter spot, scheduled breaks, and no driving while dizzy. Some barriers are medical, like lingering symptoms, trouble concentrating, or nobody explaining what to do. Others are about the employer's willingness to adjust and whether the person feels their doctors are on their side. A plan that ignores the second group tends to stall.

Can workplace concussions be prevented?

Many can. Falls and falling objects cause a large share of them, so the fixes are ordinary ones. Clear tripping hazards, keep walkways open, sign wet floors, use handrails, keep step stools where people would otherwise stand on chairs, take care on ladders, and wear the protective gear. When someone is coming back after a concussion, it is worth fixing whatever hazard caused it.

When should you see a doctor about concussion symptoms?

• Immediately for any of the red flags listed above.
• Within a day or two of any head injury, for an initial assessment, especially before driving or returning to safety-sensitive work.
• If symptoms are not clearly improving after two to four weeks, or if they are worsening with activity despite pacing.
• If headache, neck pain, dizziness, sleep problems, or low mood last beyond a month. Each of these can be treated, and specific therapy beats waiting.

Ask for a graded return-to-activity plan and, if you work, a written return-to-work plan. Pain that has outlasted the injury may respond to the same approaches used for other chronic pain. Our free screener can help you think through whether that fits you.