Fourth Quarter 2017


By: Heather MacKinnon

Question: Under Illinois law, can an impairment rating be submitted into evidence and how effective are the ratings in mitigating permanency exposure?

Short Answer:  Yes.  In Illinois, for injury dates after September 1, 2011, the parties may submit an AMA impairment rating pursuant to the most recent edition of the AMA Guidelines (now 6th edition, second printing) for consideration by the arbitrator in determining permanent partial disability.  Prior to this date, such impairment ratings were not legally relevant to permanency determinations.  If admitted into evidence, the arbitrator must weigh the impairment rating along with four other factors (see discussion) in determining permanent partial disability.  To date, the impairment ratings have not lived up to an across-the-board, meaningful decrease in permanency awards but have more modestly helped to lower permanency settlement values and trial awards.  A case-by-case analysis is necessary to properly measure the true impact of an impairment rating on a given injury.


The Act specifically states that, for injuries on and after September 1, 2011, the arbitrator shall consider the following factors when determing an award for permanent partial disability (PPD) benefits:

  • the reported level of impairment pursuant to subsection (a)- AMA rating;
  • the occupation of the injured employee;
  • the age of the employee at the time of the injury;
  • the employee’s future earning capacity; and
  • evidence of disability corroborated by the treating medical records.

820 ILCS 305/8.1b(b).

In 2011, the appellate court ruled on the issue of whether an AMA rating report must be submitted into evidence. In Corn Belt Energy Corp. v. Illinois Workers’ Compensation Commission, 56 N.E.3d 1101 (App. Ct. 3d Dist. 2016),  the appellate court held in a case of first impression that section 8.1b did not require the claimant to obtain and introduce into evidence an AMA impairment rating report. The court decided the language of the Act made the introduction of an impairment rating optional for either party. However, the court explained that when an AMA rating report is submitted, the court must consider it along with the other factors in determining permanent partial disability.

It is now clear from additional Illinois appellate court decisions that, in determining the level of permanent partial disability, the significance of and weight to be attached to each of the enumerated factors is left to the discretion of the Commission, whose determination in this regard will not be disturbed unless against the manifest weight of the evidence.

In Continental Tire of the Americas, LLC v. Illinois Workers’ Compensation Com’n, 397 Ill. Dec. 915, 43 N.E.3d 556 (App. Ct. 5th Dist. 2015), the claimant slipped and fell at work sustaining a wrist fracture and was eventually released to return to work full duty with no restrictions. At arbitration, the employer offered an AMA impairment report which indicated claimant’s impairment rating was zero. The claimant did not offer an AMA impairment report.  The arbitrator awarded permanency of 5% loss of use of the hand. The Commission affirmed and the employer appealed, arguing that the AMA impairment rating of zero precluded consideration of the remaining four factors contained in Section 8.1b(b) as a matter of law. The Appellate Court, Workers’ Compensation Division, affirmed the Commission’s decision finding that Section 8.1b(b) required consideration of all factors and that no single factor is determinant of permanent disability.

Unfortunately, the introduction of impairment ratings has not led to a significant decrease in permanency awards.  The greatest positive impact has been with regard to carpal tunnel cases at the wrist in the repetitive trauma context, but operated knees, shoulders and backs are closer to more traditional permanency values even when an impairment rating is introduced.  A case-by-case analysis is needed to assess whether an impairment rating will have a meaningful impact on permanent partial disability to justify its cost.

Practice Tip:  It is beneficial for an employer to consult the AMA guidelines to determine the likely impairment rating for a given injury, and then to further assess whether the impairment rating, along with the other enumerated factors, will materially lower permanent partial disability for a given injury.  Since enactment, decisions are being rendered to provide some level of guidance on case values in this era of impairment ratings.  Often, the mere threat of a potential impairment rating is enough to give additional leverage to settle a case below traditional value without incurring the actual cost of the impairment rating.