Catastrophic Impairment and The Glasgow Coma Scale

Catastrophic Impairment and The Glasgow Coma Scale

The definition of a catastrophic injury or “catastrophic impairment” (under the Statutory Accident Benefits Schedule -”SABS”) has recently undergone changes.

Catastrophic injuries are those injuries that have serious, long-term physical and emotional impact on the lives of the victim. Traumatic brain injuries and brain impairment are amongst those injuries that commonly fall within the definition. The definition of “Catastrophic Impairment” includes a score of 9 or less on the Glasgow Coma Scale; or a score of 2 or 3 on the Glasgow Outcome Scale.

Glasgow Coma Scale

The Glasgow Coma Scale is a neurological scale used to measure the severity of a Traumatic Brain Injury (TBI). A series of symptoms are outlined and given a numeric score. After adding up the numeric scores of each symptom, the total score is used as an indication of how severe the brain injury is.

Eye Opening / Eye response
No Opening = 1 (most severe)
Eyes Open To Pain = 2
Open in Response To Speech = 3
Eyes Open Spontaneously = 4
Verbal Response
No verbal Response = 1 (most severe)
Response Verbally To Sounds = 2
Response Makes No Sense = 3
Response is Confused = 4
Responds with Conversation = 5
Best Motor Response
Response to Pain Stimulus:
No motor Response = 1 (most severe)
Generalizing (abduction of arm, extension of wrist, decerebrate response) = 2
Arm Extension (adduction of arm, flex-ion of wrist, decorticate response) = 3
Arm Flex-ion (withdraws in response to pain) = 4
Localizes to Pain (purposeful movement toward pain stimuli) = 5
On Command = 6
GCS Total: 3-15
Generally, a brain injury is classified as either Severe, Moderate or Minor.
Less than 8 on GCS = Severe
Between 9-12 on the GCS = Moderate
Greater than 13 (13-15) on the GCS = Minor

Description of Terms

Adduction – is a movement which brings a part of the anatomy closer to the middle sagittal plane of the body. It is opposed to abduction.

Decerebrate – posturing is also called decerebrate response, decerebrate rigidity, or extensor posturing. It describes the involuntary extension of the upper extremities in response to external stimuli. In decerebrate posturing, the head is arched back, the arms are extended by the sides, and the legs are extended. A hallmark of decerebrate posturing is extended elbows. The arms and legs are extended and rotated internally. The person is rigid, with the teeth clenched. The signs can be on just one or the other side of the body or on both sides, and it may be just in the arms and may be intermittent. A person displaying decerebrate posturing in response to pain gets a score of two in the motor section of the Glasgow Coma Scale.

Decorticate – posturing is also called decorticate response, decorticate rigidity, flexor posturing, or, colloquially, mummy baby. Patients with decorticate posturing present with the arms flexed, or bent inward on the chest, the hands are clenched into fists, and the legs extended and feet turned inward. A person displaying decorticate posturing in response to pain gets a score of three in the motor section of the Glasgow Coma Scale.

Abnormal posturing – is an involuntary flexion or extension of the arms and legs, indicating severe brain injury. It occurs when one set of muscles becomes incapacitated while the opposing set is not, and an external stimulus such as pain causes the working set of muscles to contract. The posturing may also occur without a stimulus.Since posturing is an important indicator of the amount of damage that has occurred to the brain, it is used by medical professionals to measure the severity of a coma with the Glasgow Coma Scale (for adults) and the Pediatric Glasgow Coma Scale (for infants).

The Glasgow Outcome Scale (GOS)
Was widely used before other scales were developed and may still be referenced in some Traumatic Brain Injury literature. The categories of the original scale were as followed: dead, vegetative, severely disabled, moderately disabled, and good recovery. An extended version of the scale divided each of the last three categories in two, making a total of eight categories.