While I'm not certain about Michigan, everywhere I've lived, the first question medical receptionists ask when making an appointment is whether the issue arises from a work injury or a car accident. They ask this because those events are covered by insurance other than your regular medical insurance: Workers Compensation and Auto insurance, respectively.
The one time I sought medical attention after a car accident, it was covered by my auto insurance, not my usual health insurance.
Thus, I suspect it's your auto insurance that pays, depending on the coverage you have. But, of course, you should verify this with both your auto and health insurers to be sure.