Head injuries in Australia 2020–21

Head injuries are a major cause of hospitalisation, disability, and death in Australia. Effects can range from temporary or short-term impacts through to permanent and severe disability or death. A head injury can encompass injuries of all severities and care requirements, ranging from a small cut to a traumatic brain injury (TBI).

Short-term effects can include loss of consciousness, amnesia, headaches, sensitivity to light and disorientation. Permanent effects include Acquired Brain Injury (ABI) in the form of changes in physical, cognitive and sensory functioning, personality, speech, behaviour, sleeping patterns, memory, seizures, and mental health (Health Direct 2021, Synapse 2023).

In this report, head injuries are broadly defined as those due to an external cause where the site of injury is the head, or both head and neck. This is different to Acquired Brain Injury (ABI) which describes disability arising from any damage to the brain that occurred after birth (AIHW 2007).

Common causes of ABI include accidents, stroke, lack of oxygen and degenerative neurological disease. A subset of ABI, Traumatic Brain Injury (TBI) involves an external assault to the head that results in damage to the brain or an alteration in brain function (Helps et al.  2008). This might result from a blow or blunt force (perhaps caused by an assault or a fall), or may be caused by rapid back and forward motion such as might be experienced in rapid or sudden deceleration (as in a motor vehicle accident).

In 2020–21, head injuries resulted in:

The impact of a head injury may extend beyond the individual, through to family and support networks as well as an increased load on the health system. Traumatic brain injuries (TBIs) alone are estimated to have a lifetime cost between $2.5 million to $4.8 million per individual (Department of Health and Aged Care 2019).

Most head injury events are preventable (AIHW 2023b). Injuries may be:

• unintentional – causes include falls, contact with objects, and transport accidents
• intentional – caused by assault, homicide, self-harm and suicide
• of undetermined intent.

Further details on each of these categories of injury are included in Injury in Australia.

Scope

This report presents information on the 406,000 head injury related emergency department (ED) presentations, 142,000 hospitalisations and the 2,400 deaths between 1 July 2020 to 30 June 2021. Deaths that occurred during hospitalisation may be counted in both the hospitalisations and deaths data. Deaths recorded in National Coronial Information System (NCIS) data may also be counted in the National Mortality Database (NMD) data. While the NMD includes both open and closed cases from the NCIS, analysis of the NCIS database only includes closed cases, which accounts for the smaller number of deaths among these records.

In this report, head injuries are defined as any hospitalisation or death due to an external cause where the site of injury is the head, or head and neck. Where the site of injury is only the neck, cases are excluded from this report.

Head injury hospitalisations were included if they were recorded as:

• The principal diagnosis. The principal diagnosis is established after study to be chiefly responsible for occasioning an episode of admitted patient care (AIHW METEOR).
• An additional diagnosis. Additional diagnoses are the one or more conditions or complaints either coexisting with the principal diagnosis or arising during the episode of admitted patient care (AIHW METEOR).

4 in 5 head injury hospitalisations in 2020–21 involved head injury as the principal diagnosis. The head or neck was the body part most often identified as the main site of injury in all injury hospitalisations in 2020–21 (AIHW 2023b), which to some extent probably reflects the serious nature of head and neck injuries.

This report does not include information on head injuries that did not result in an ED presentation, hospitalisation or death. There are many more cases that are treated by general practitioners, allied health professionals or outpatient clinics that are not reflected in this report. Methods for identifying and counting head injury hospitalisations and deaths are detailed in the technical notes accompanying this report.