In cases of work-related injuries, the insurance company has a right to request that you be examined by a doctor of their choosing to determine the extent and validity of your injuries. This doctor who is examining you is not your treating doctor and is only doing so for the insurance company. Their bill will be paid by the insurance company. Again, they will not be treating you nor are they obligated to tell you what their findings and recommendations are at the time of your examination. Sometimes these appointments can be cold and unfriendly as the doctors are unwilling to provide much information if any at all. Obviously, this is very different than our typical experience with doctors and physicians. Please keep in mind that it is fine for you to be slightly apprehensive, but it is imperative that you cooperate and be truthful with the doctor.
For more information, check out this article.