The WorkCover Tasmania Guidelines to Impairment Assessment that modify the American AMA  (4th Edition) Guides are used to assess impairment of Tasmanian workers.

Without going into some more fundamental issues about the use of impairment assessment systems (such as the validity of any system that attempts to quantify injury in percentage terms or the reasons for exclusion of pain as a separately assessable impairment), there are two areas of current concern about the Tasmanian Guides.
Perhaps the issue of greatest concern is the effect that a spinal impairment rating can have on an insurer’s willingness to approve spinal surgery procedures.

With the latest editions of the Guides (Version 2 & 3) fusion or disc replacement surgery is considered to meet the criteria for ‘multilevel structural compromise”. This automatically is rated as DRE category IV or V. This is 20% and 25% Whole Person Impairment (WPI) respectively in the lumbar spine and 25% and 35% WPI in the cervical spine. In the absence of surgical intervention most spine injuries are rated at 5% or 10% WPI and only the most severe injuries with associated spinal cord damage are rated above that level.

Under Tasmanian workers compensation legislation there is a threshold for access to Common Law. Workers with injuries rated at 20% WPI (previously 30%) and above have access to common law damages. Insurers considering a recommendation to fund spinal fusion or disc replacement surgery are faced with the potential ‘double whammy’ of the not insignificant costs of the surgery and the prospect of a higher impairment rating opening the door for the worker to common law entitlements and higher lump sum payments for permanent impairment. In addition, there are often concerns that the surgery may not have a positive outcome in terms of getting the worker back to work. Understandably insurers hesitate to fund spinal surgery.

My concern as a doctor managing work injuries is that the current impairment guidelines for assessment of spinal impairment can create a barrier to appropriate surgical intervention in some cases. The solution lies in a review of spinal impairment criteria, that recognises the effects of fusion and disc replacement on the structural integrity of the spine, but does not equate a more functional spine post operatively to an impairment category higher than that of a dysfunctional spine prior to surgery. This might require both a review of spinal impairment ratings for spinal conditions associated with disabling pain who have not had such surgery and spinal conditions where surgery has been undertaken. The important issue is that WPI ratings per se should not act as a disincentive to insurers to approve necessary spinal procedures. Spinal surgery should only be considered on the medical merits of the proposed procedure.

The other issue of concern is the assessment of impairment associated with Complex Regional Pain Syndrome (CRPS), previously known as Reflex Sympathetic Dystrophy (RSD). The WorkCover Guides have strict criteria before a worker can be assessed using the specific methodology for assessing impairment associated with CRPS. The diagnostic criteria in the guides are not based on the internationally accepted diagnostic criteria for CRPS. Only severe cases of CRPS meet the criteria. The most common scenario is that the clinical diagnosis of CRPS is clear, often agreed by both the treating practitioners and independent assessors, yet the prescribed methodology for assessing the disorder cannot be used. This is a situation where the Guidelines do not align with current clinical practice. This results in artificially low impairment ratings for a disorder which can result in a permanent disorder with a very high level of disability. The solution here is clear, the diagnostic criteria for CRPS included in the impairment guidelines should be brought into line with current clinical practice.

While I am not as familiar with the WorkCover Impairment Guidelines in other states (Victoria does not have statutory guidelines, only AMA4), I suspect the same issues might arise there too.