What areas are affected with a motor Glasgow Coma Scale (GCS) score of 4?

From the Guidelines

A motor Glasgow Coma Scale (GCS) score of 4 indicates abnormal flexion in response to painful stimuli, reflecting significant brain dysfunction, typically involving the cerebral cortex, internal capsule, and corticospinal tracts, which control voluntary movement. This level of motor response suggests a moderate to severe brain injury, often seen in conditions like traumatic brain injury, stroke, hypoxic-ischemic encephalopathy, or increased intracranial pressure 1. The areas affected with a motor GCS score of 4 may include:

• Frontal and parietal lobes, which control voluntary movement
• Internal capsule, which transmits motor signals from the brain to the spinal cord
• Corticospinal tracts, which transmit motor signals from the brain to the spinal cord
• Deeper brain structures, which may be relatively preserved despite the significant brain dysfunction. The total GCS score (combining motor, verbal, and eye-opening components) would help determine the overall severity of neurological impairment. Patients with this motor score require immediate neurological assessment, airway protection, and management of intracranial pressure if elevated, as sedation and pain medication may influence the assessment of the GCS motor score 1. Continuous neurological monitoring is essential as deterioration in motor response can indicate worsening brain injury requiring urgent intervention.

From the Research

Areas Affected with Motor GCS Score of 4

The motor component of the Glasgow Coma Scale (GCS) is a critical aspect of assessing neurologically compromised patients. A motor GCS score of 4 can represent different combinations of motor, verbal, and eye responses, which may have varying mortalities 2.

• The areas affected with a motor GCS score of 4 can include:
  • Limited ability to follow commands
  • Inability to perform complex movements
  • Presence of flexion or extension posturing
  • Decreased level of consciousness
  • Potential for severe injury or poor neurologic outcome 3, 2, 4, 5

Predictive Value of Motor GCS Score

The motor component of the GCS has been shown to be a strong predictor of neurologic outcome and mortality in patients with traumatic brain injury or out-of-hospital cardiac arrest 3, 2, 5.

• A motor GCS score of 4-5 has been associated with a higher odds ratio of good neurologic outcome at 90 days in patients with out-of-hospital cardiac arrest 3.
• The motor component of the GCS has been found to contain virtually all the information of the GCS itself and can be measured in intubated patients, making it a useful tool for predicting outcomes in trauma patients 2, 4.