Compensation that one may be awarded in a personal injury case can be divided up into the following categories:
For example, you are entitled to the full repair or replacement cost of your vehicle.
Medical Expenses to Date
If someone else has been paying your medical bills, like your health insurance plan, you do have to pay them back. That's called subrogation and there are circumstances where a lawyer can help you avoid the payback.
The basic rule is: you are entitled to have your medical bills to date paid in full.
Future Medical Expenses
You are entitled to a sum of money which will be sufficient to pay future medical bills. A lawyer can help design a number of different systems. For example, you could have a system where you keep your receipts and submit them for payment at the end of each year, but insurance companies want to have claims closed once and for all.
So instead, you get a one time lump sum payment for all future medical care. That means you need to get an estimate of the cost of future care like you would get an estimate for the cost of fixing a car except the human body is much more complicated.
Your lawyer will have to obtain from a doctor a diagnosis (what is the injury), a prognosis (what is likely to occur in the future), a treatment plan (what specific medical care will more likely than not be needed in the future) and then convert that to a dollar figure representing future medical care.
Lost Wages to Date
Relatively easy to prove, it's just a matter of data collection.
Lost Future Earning Capacity
If you are temporarily or permanently, partially or completely unable to work, you are entitled to a lump sum representing the difference between the amount you could have earned before the injury and the amount you can earn now.
That's easy if you have a long term, full time job, you can no longer do. It is harder if you are a fisherman, or a realtor, or self employed. It is also harder if you suffer only a partial loss.
Your lawyer will take your medical records to experts in physical capacity evaluation and vocational rehabilitation, quantify the impact of the injury on employment, and then obtain a written opinion from an economist, an expert in economic loss.
In sum, you are entitled to a lump sum representing the difference between the amount you could have earned before the injury and the amount you can earn now.
General Damages for Pain, Suffering, Disability, or Disfigurement
The other 5 items of damages are easy to add up:
You can buy all those things, but there is no market for pain.
You could put a thousand people up against a wall and ask "How much would I have to pay you to be run over by a truck and have your back broken?" Nobody is going to volunteer for a thousand dollars or a hundred thousand dollars. People won't volunteer for a life changing injury for a million dollars.
But you are entitled to be compensated for a life changing injury. Your lawyer will have to convince a jury or the insurance company of the impact of the injury on your life. That is a difficult assignment, but it is one a competent and experienced personal injury attorney will have successfully completed on many occasions.