There is no single legal checklist, but a catastrophic injury generally means one with permanent, life-altering consequences — an injury that changes a person's ability to live, work, and function for the rest of their life. The classic examples are traumatic brain injuries, spinal cord injuries and paralysis, amputations, and severe burns.
What sets these apart from ordinary serious injuries is the permanence and the future. A broken bone that heals, however painful, is usually not catastrophic; an injury that leaves lasting impairment, requires lifelong care, or ends the ability to earn a living is. Loss of a major sense, like sight or hearing, and severe disfigurement also fall in this category.
The label matters because it changes how the case must be built. A catastrophic claim has to account for the entire future — decades of medical care, lost earning capacity, equipment, and changed circumstances — documented with medical, life-care, and economic experts, rather than just the bills incurred so far.