The workers’ compensation commissioner may appoint a duly qualified, impartial physician to examine the injured employee and make report. The fee for this service shall be five dollars, to be paid by the workers’ compensation commissioner, together with traveling expenses, but the commissioner may allow additional reasonable amounts in extraordinary cases. Any physician so examining any injured employee shall not be prohibited from testifying before the workers’ compensation commissioner, or any other person, commission, or court, as to the results of the examination or the condition of the injured employee.