Concussions are traumatic brain injuries.  In fact, 90% of traumatic brain injuries are concussions.  The remaining 10% are classified as moderate to severe brain injuries.

The US Center for Disease Control and Prevention (CDC) states without qualification,

“the term mild traumatic brain injury (MTBI) is used interchangeably  with the term concussion.”

The CDC also recognizes that concussion injuries do involve damage to brain cells and, therefore, are brain injuries:

“A concussion is a type of traumatic brain injury-or TBI-caused by a bump, blow, or jolt of the head or by a hit to the body that causes the head and brain to move rapidly back and forth. This sudden movement can cause the brain to bounce around and twist in the skull, creating chemical changes in the brain and sometimes stretching and damaging brain cells.

The American Medical Society for Sports Medicine agrees, defining a concussion as a subset of mild traumatic brain injury,

“a traumatically induced transient disturbance of brain function (involving) a complex path though physiological process”.

The most well-accepted definition is that established by the American Congress of Rehabilitation Medicine’s Special Interest Group is:

Definition: a patient with mild traumatic brain injury is a person who has had a traumatically induced physiological disruption of brain function, as manifested by at least one of the following:

    1. Any period of loss of consciousness;
    2. Any loss of memory for events immediately before or after the accident;
    3. . Any alteration of mental state at the time of the accident (e.g. Feeling dazed, disoriented, or confused); and
    4. Focal neurological deficits that may or may not be transient.

This definition includes:

    1. The head had been struck
    2. . The head striking an object, and
    3. The brain undergoing an acceleration-deceleration movement (i.e. whiplash) without direct external trauma to the head.

Note: Any alteration of mental state resulting from a force that causes a “whiplash” of the brain qualifies as a concussion!