I have been critical of arguments used in Independent Medical Examiner (IME) reports to justify opinions that a work injury (or an activity at work) is no longer the “cause” of an ongoing disabling condition. My criticism is based on the faulty logic of those opinions under our current legal system, not because I have no sympathy or concern for the employer found to be liable when those arguments fail.
One of the most common opinions expressed in defendant IME reports is that the effects of a work injury have ceased and that any ongoing symptoms are due to an underlying degenerative condition.
The spurious argument
There is an underlying asymptomatic degenerative disease, usually evident as imaging changes. No argument with that! Although there is an acceptance by the IME that an injury, event or a work activity triggered the claimed condition, the opinion is, that despite continuing symptoms, the effects of the injury or work activity have ceased (or will cease at some future time). Therefore any continuing symptoms (and associated disability, work incapacity or need for treatment) are solely due to the underlying condition which is unrelated to work. It is argued that the effects of the claimed injury can only continue for a finite period of time, often on the basis that the inciting injury was minor.
It is the latter arguments that fail the test of logic. I know of no evidence to support the idea that the duration of symptoms following an injury in a compensation system can be accurately predicted, nor evidence about the likely timing of onset of symptoms from an asymptomatic degenerative disorder. Certainly the IME’s who use these arguments do not present any evidence in support. There are however well accepted mechanisms for persistent pain that can explain chronicity of symptoms irrespective of the severity of any initial tissue damage.
What is fair?
I do have sympathy for the insurer or employer where a claim is made for a seemingly minor incident at work on a background of gross reportedly asymptomatic degenerative disease and the claimant develops long-term incapacity. The employer has to cover treatment, including expensive surgical procedures and income support costs and perhaps a significant payment for permanent impairment.
From a medical perspective, the most significant cause of the claimed condition might well be the worker’s genetic makeup and their life-time of wear and tear activity. The ‘straw’ that breaks the proverbial ‘camel’s back’ (or in the situation being discussed here, the ‘insurer’s purse’) is often a fairly inconsequential injury or event at work, or even onset of symptoms in the course of normal work activity.
Workers compensation liability determination however works within a legal framework. In most jurisdictions, an ‘injury’ arising in the course of employment is all that is required for liability to be placed on the employer for treatment, lost income and permanent impairment. It doesn’t matter much how significant the injury was, or whether there were predisposing factors, if the person was previously asymptomatic, there is a good chance that the employer will be found liable.
Furthermore there is the principle of benevolent interpretation, especially when it comes to impairment assessment. For example, in the current version of the Tasmanian WorkCover Guides to the Assessment of Impairment, the following appears:
‘If there is objective evidence of a pre-existing symptomatic permanent impairment in the same region at the time of the work-related injury, then its value should be calculated and subtracted from the current whole person impairment value. If there is no objective evidence of pre-existing symptomatic permanent impairment, then its possible presence should be ignored.’
The reference to ‘symptomatic’ in the final sentence above is true benevolence, because for a pre-existing condition to be considered significant and taken out of consideration it has to symptomatic, in addition to the requirement for objective evidence of its existence.
Presuming that the worker is telling the truth (and that is not always correct) there are adequate medical explanations for persistent pain following injury i.e. the mechanisms of neural sensitisation and the influence of psychological factors on those processes. It is perhaps wishful thinking that a doctor can arbitrarily state that the effects of the injury have ceased and that the persistent pain and disability has somehow reverted to being due to the underlying condition even if the process had previously been asymptomatic. The ‘but for’ test comes into play from a legal perspective i.e. ‘but for’ the injury/event/work activity, is it likely that the worker would have the current symptomatic condition?
In reality, in most cases, the only logical answer is that without the work injury/event/work activity the worker would not have the symptomatic condition and therefore the employer is legally liable. It is a separate question as to whether that is fair. As our workforce ages with the expectation from our politicians that we will all work longer and longer these issues will become more and more common.
In my opinion it is usually a nonsense when an IME assessor uses the argument that the effects of a precipitating event has passed and that a previously asymptomatic condition has now taken over as the cause. It doesn’t make medical sense, nor is it ‘common sense’.
The real question?
What is needed to avoid employers becoming unfairly liable for degenerative disease resulting from genetic predisposition and a lifetime of wear and tear?
While it will be a difficult task to change currently well-accepted definitions of causation established by statute and common law, such changes are essential to ensure the burden of occupational injury and disease is fairly borne by employers. Maybe any change will open up a whole new opportunity for legal argument! I certainly hope not.
There are many conditions where work is the cause, but no claim is lodged, or claims are legislatively excluded, particularly burgeoning workplace psychological ill-health issues. If the system is to fairly deal with these conditions, which it does not at present, measures need to taken to reduce the burden on employers from unfair liability for degenerative musculoskeletal disorders.
A change to the legal definition of injury such that medically recognised contributing factors can be taken into account in determining liability, even for previously asymptomatic conditions.