concussion
A brain injury caused by a hit to the head, face, neck or body that makes the brain move quickly inside the skull. It changes how the brain works for a while.
sign
Something other people can see, such as a blank stare or trouble with balance.
symptom
Something the injured person feels or notices, such as a headache or feeling "in a fog".
red flag
A sign or symptom that could mean a more serious injury. Call 911 right away.
relative rest
Resting for the first day or two while still doing gentle everyday things at home, with limited screen time.
medical clearance
A note from a doctor or nurse practitioner saying the person is ready to go back to full-contact practice and games.
second impact syndrome
A rare but very dangerous swelling of the brain that can happen if a person gets another concussion before the first one has healed.