Minor head injury occurs very frequently in children.

1. Very common type of trauma to the head.
2. Some children show an atypical cerebral concussion not frequently observed in adults.
3. An epidural hematoma must not be overlooked.

Depending on the age, minor head injury results from different causes:
Infants: Falls, incidental injuries.
Toddlers: Self-inflicted falls at home and on playgrounds.
Schoolchildren: Vehicular and pedestrian accidents, injuries incurred in various types of sport, or blows received.

In contrast to the severe head injury, in minor head injury the acute de- and acceleration is of lesser degree and does not occur repeatedly. The resulting cerebral concussion exhibits no long-lasting and irreparable brain damage on conventional histological examination.
In case of pre-existing migraine, minor head injury may trigger an attack of migraine, which explains some cases with an atypical cerebral concussion.

The diagnosis of a mild traumatic brain injury is a clinical diagnosis and includes:

• An initial unconsciousness lasting seconds to minutes
• and/or a clouding of consciousness lasting 1 hour at the most
• an obligatory posttraumatic amnesia lasting minutes to less than 24 hours
• GCS 13-15

For practical purposes the following arbitrary definition may be used:
In the most severe form of cerebral concussion the initial unconsciousness does not last longer than fifteen minutes, and the following clouding of consciousness not longer than one hour. In case of a longer lasting unconsciousness and/or clouding of consciousness a cerebral contusion or other pathology has to be considered.

The history should find out the mechanism of injury, the child's behavior following the accident, and a possible amnesia. Besides an observed clouding of consciousness, confusion, dizziness, disorientation, apathia, inattention, and inability to solve successive daily tasks may point to a suffered cerebral concussion.
Because a continous observation of the child following an accident is usually impossible, an amnesia as an indication of loss of consciousness can be only recognized in schoolchildren, and because mild cerebral dysfunction (as known from adult athletes) may escape the observation, it is possible that the diagnosis of cerebral concussion in a toddler is missed.

At clinical presentation there is no or only a minimal clouding of consciousness (Glasgow coma scale 15 to 13) and the neurological examination is normal. Scalp and facial lacerations, abrasions, hematomas and autonomic nervous signs such as vomiting, paleness and profuse perspiration point to the head injury.

In atypical cerebral concussion the clinical signs are more impressive: A short unconsciousness is followed by a long-lasting clouding of consciousness with or without distinct fluctuations of the state of consciousness. In the former situation the children can be awakened for a short time, or sometimes not at all even with a painful stimulus. The described course may also be observed following a latent period with or without an initial unconsciousness.
In addition, often transient neurological and severe vegetative signs may be observed, or without clouding of consciousness as in amaurosis fugax. No later than 24 hours after the event, there is a complete recovery except for vegetative signs.

In the majority of the children there is a complete recovery. A postconcussional syndrome may be observed with neurovegetative and psychoorganic symptoms and schooling problems.
Sometimes, an early epileptic fit occurs in the first hours after the injury, which overlaps the clinical signs of cerebral concussion, and the injury may be assessed erroneously as more severe.

In typical concussion the differential diagnosis is only important if the history of trauma is not known, or if an early epileptic fit occurs.
In atypical concussion all pathologies with clouding of consciousness and/or neurological signs must be considered:
Cerebral contusion, epidural and other intracranial hematomas, intoxication with drugs and ethyl alcohol, and hysteria should be excluded.
In some of the children (but not in all) with atypical concussion an acute confusional migraine explains the clinical presentation, especially if there is a family history of migraine and a history of motion sickness, migraine or headaches of the patient.

In suspected fracture of the skull (history of a typical trauma, incidental injury, age 0.6 to 2 years, characteristic findings) skull x-rays in one or two planes, special x-rays and/or CT without/with reconstruction are performed; CT in suspected epidural hematoma or cerebral contusion.

Depending on the history, the clinical findings and the follow-up.
Every case of minor head injury should be followed during the next 24 hours with distinct advices; the modalities (supervision by the parents, or as out- or in-patient) depend on the individual case and other factors (for instance the reliability of the parents, and the distance from the hospital).
A normal CT at the beginning does not guarantee a normal outcome in the next 24 hours without observation.

See 'natural history' above.