Good question - it should not make any difference because the fact that you had a pre-existing condition does not relieve the driver who rear-ended you of liability for your injuries from the crash. However, this is definitely a situation where you should not try to go it alone with their insurance company. The first thing they will do is take a statement, and usually they will ask about past medical issues. Also, they will require you to sign a medical release which allows them to go digging into your prior medical records. Insurance companies are notorious for using prior medical issues as a reason to devalue a claim. You should contact a personal injury attorney in Denver right away for representation.
Merry Fountain is licensed to practice law in Indiana. She can be contacted at 1-888-242-HURT. This is not legal advice and it does not create an attorney/client relationship. It is legal education intended to provide general information about the matter within the question. If the question does not include important timeframes and facts the answer could change. Merry Fountain strongly advises the questioner to confer with an attorney in your state.
You are not required to deal directly with the insurance carrier and its adjusters. Engage experienced counsel and let counsel deal with the folks who want to minimize your pain and need for treatment. You deal with counsel and focus on getting better.
Under Colorado law the driver at fault will be responsible for any exacerbation of your pre-existing injuries. To the extent that he can't differentiate the injuries he will be liable for the whole amount of damages.
The closed head injury can be more problematic. Was there loss of consciousness, dizziness, loss of balance. These symptoms can be signs of a more serious problem.
You should seek legal counsel and not make any statements to insurance companies until you do.
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