The Medical Disability Society Working Party Report on the Management of Traumatic Brain Injury (1998) defines Traumatic Brain Injury (TBI) as a “Brain injury caused by a trauma to the head (including effects upon the brain of other possible complications of injury; notably hypoxemia (reduced oxygen in the blood), hypotension (low blood pressure) and intracerebral haematoma (bleed))” i.e. damage caused initially from an outside force but including the complications that may follow this force.

Traumatic brain injury is often incorrectly referred to as Acquired Brain Injury but this form of brain injury reports to that caused by conditions such as strokes and cerebral palsy. Traumatic brain injury is a prolonged chain of events from the effects of the initial injury to subsequent secondary and tertiary events happening over a time-course of minutes, hours, months and even years in some cases. Often the effects of TBI only become apparent as a result of new challenges to the patient and during the ageing process.

Traumatic brain injury is a major disorder of public health significantly affecting physical, cognitive and psychosocial functioning. It is the leading cause of death and disability worldwide especially in young adults and children and the leading cause of seizure disorders. In Europe there are approximately 1,000,000 admissions per year of which 300,000 are directly as a result of sporting injuries (including 20,000 from winter sports). The estimated published incidence rate is 100 per 100,000 population meaning approximately 59,000 new injuries per year in the UK. The highest incidence rate falls in the 15-24 age group, those over 75 years of age and a slight peak in children below 5 years of age. In the US every 21 seconds someone suffers a head injury. Prevalence rates (total number of existing patients living with TBI) in the UK range from 450,000 to 1,160,000 estimated patients. Because mild TBI is very often unreported and therefore significantly under-diagnosed the extent of TBI is probably much greater.

Traumatic brain injury has huge economic consequences; it is estimated that in the US the cost of acute care and subsequent rehabilitation of new patients per year reaches $9-10 billion. In addition, estimates for the life-time cost per severe TBI patient are considered to vary between $600,000 and $1,875,000. The total cost to the US Healthcare System was estimated to be $56 billion in 1995.

The principle causes of brain injury are through vehicular accidents including motorbikes, bicycles and pedestrian collisions (50%); falls, especially in the elderly and young children (27%); acts of violence (20%) and sports injuries (3%). Two thirds of brain injuries occur in the under 30 year old age group and two thirds of brain injury survivors live a normal lifespan.