Criminal Law Questions? Ask a Criminal Lawyer.
Absolutely. There are many varieties and types of fraud/theft/etc so if you provide a bit more information I can give you more specifics.
There's an article I want you to read...
Please understand that workers compensation fraud is a serious issue that could be prosecuted in a variety of ways and have severe consequences. While I do not know the details of your case, you indicated that you were accused of not disclosing a preexisting condition that had nothing to do with your injury. This sounds to me like a scare tactic to get you to settle a claim for less than it is worth. You should not let them scare you into a settlement that is unjust.
You need a lawyer. Insurance companies are notorious for abusing people in settlement proceedings. You need someone to work with you and help you get what is just and fair... do not let them scare you into submission.
Your lawyer will help you settle your claim fairly and protect you from criminal prosecution. If your prior injuries had nothing to do with the present injury and you did not hide it to increase your workers compensation settlement then you are not likely guilty of any crime.
Get a lawyer.
Please reply if I can help further.