If your work-related injury has left you with permanent medical restrictions that prevent you from performing the job that you held prior to your injury, there's a good chance that any new job you might find that allows you to work within your new restrictions will pay less than what you were earning at the time of your injury.  In this situation, you may be entitled to Wage Differential benefits under Section 8(d)1 of the Illinois Workers' Compensation Act.  

In order to be eligible for Wage Differential benefits, you must first prove that your work injury has left you with:

(1) a partial incapacity that prevents you from returning to your usual and customary line of employment; and

(2) an impairment in earnings.

If these elements can be established, then you would be entitled to receive compensation equal to 2/3 (66 2/3%) of the difference between the amount that you would have been able to earn in the full performance of your pre-injury job and the amount that you are now able to earn in your new job.  For injuries that occurred before September 1, 2011, Wage Differential benefits must be paid for the duration of the disability.  For injuries that occur on or after September 1, 2011, benefits will be paid for five (5) years after the date of the award or until you reach age 67, whichever is later. Unfortunately, you can only be compensated for either the loss of wages or the permanent disability related to the same injury, but not both.

For a more detailed explanation of Wage Differential benefits under the Illinois Workers' Compensation Act, please read Making Up the Difference: Wage Differential Claims Under the Illinois Workers' Compensation Act, written by Shawn M. Robin for the Illinois Trial Lawyers Association's Trial Journal (Summer 2012).