Final answer:
The ISS score cannot be accurately determined for patients with an AIS 9 injury because an AIS 9 indicates a fatal injury.
Step-by-step explanation:
The ISS (Injury Severity Score) is a widely used scoring system to assess the severity of multiple injuries sustained by a patient. It takes into account the six most severe injuries and assigns them a value ranging from 1 to 6. The scores are then added together to give an overall ISS score. However, an AIS 9 indicates a fatal injury, meaning the patient has already died, so an accurate ISS score cannot be achieved in this case.