What does it take to prove CRPS?
April 8, 2019
This article was originally published in October 2018 by the Personal Injury Law Journal published by Legalease Limited.
I pose the question because in a case called Ruffell v Lovatt in April 2018, a county judge – the designated civil judge in Winchester, HHJ Iain Hughes QC – found that CRPS or ‘complex regional pain syndrome’ was a ‘controversial topic’ and the ‘subject of debate’. He also found that the medical experts instructed by the defendant had proven that CRPS is medically untestable and a controversial differential diagnosis.
The court also found that limb disuse due to immobilisation can give a similar clinical picture to CRPS. In the present case, the claimant had a profound psychiatric history of somatic symptom disorder and was also found to be an unreliable historian, but the claimant had been treated by leading experts in the country for CRPS, the same condition which she failed to prove at trial.
So, what is the truth about CRPS? Does it exist? Can it ever be proven in the medico-legal context at trial?
Firstly, some cite the Ruffell decision as evidence that the judge found that CRPS does not exist. Upon reading the judgment, the judge seems careful to have not found that CRPS does not exist. Indeed, it is not for a judge to rewrite the medical textbooks.
Secondly, I stated in Chapter 5 of my book A Practical Guide to Chronic Pain Claims that CRPS is very much towards the organic end of the spectrum but that the pathology of CRPS remains poorly understood. CRPS is thought to have a higher central nervous system origin. The key point is that CRPS only occurs in extremities, legs, arms, hands and feet rather than in the spine. Some doctors think that the anterior cingulate cortex (ACC) and periaqueductal grey (PAG), a mid-brain structure may be involved. Failure of the PAG to inhibit pain signals fails to quieten the response and the pain becomes a positive feedback cycle, encouraging the injured area to become more swollen, more painful and more inflamed due to overactivity of the parasympathetic nervous system.
CRPS has been the subject of great debate in the medical profession for decades. The condition has evolved in diagnostic criteria. The standard criteria for diagnosis are called the ‘Budapest Criteria’ but there is no minimum standard criteria to make the diagnosis. There are also two types of CRPS. Type I follows a soft tissue injury without identified specific nerve damage. CRPS Type II follows a well-defined nerve injury. The problem is that the diagnostic criteria rely in part on the patient’s self-reporting, so questions, particularly in the litigation context, arise about the validity of the diagnosis. Psychiatric factors also appear to play a role in the development and maintenance of the condition, as there is interdependence in relation to psychiatric factors with the physical factors including potentially reward and motivational factors. There is ongoing research.
Diagnosis is therefore not an easy area. Practitioners and experts who make the mistake of assuming that just because a diagnosis has been made by treating experts, such a diagnosis of CRPS will be sustained at court, may be mistaken as the judgment in Ruffell demonstrates.
It is important to remember that CRPS is a diagnosis of exclusion. Therefore, in a psychiatrically vulnerable individual such as this claimant and in the absence of easily demonstrable physical symptoms, such as gross swelling, trophic changes and visible colour changes, it seems to me that experts and practitioners alike in the litigation context should be very slow to diagnose CRPS. Particular care and justification is needed.
Somatic symptom disorder under the new DSM V criteria can be an equally valid psychiatric diagnosis which may explain the symptoms. Psychiatric symptoms are compensatable too and it seems to me that there is often a leap to diagnose CRPS when it is not the case.
It is necessary to be careful in the diagnosis but also of course not to miss true cases of CRPS, not least of course because CRPS has a small risk of spreading to other limbs, justifying potential claims for provisional damages.
It is also important to remember that most cases of CRPS however get better. 90% are better at two years post-trauma. Where symptoms continue, particularly in the context of litigation, CRPS is often replaced with functional effects. Limb disuse, conscious or unconscious, can provoke or maintain similar effects.
Quite often, the complaints of nerve pain continue but the objective signs such as discolouration and swelling are no longer seen and a diagnosis of CRPS is often no longer appropriate.
It is therefore respectfully suggested that CRPS is an over-used diagnosis and often an unnecessary and wrong one which creates unnecessary distress for the claimant. It is also one which is more difficult to prove than an alternative diagnosis. The diagnosis itself may perpetuate symptoms from a psychiatric perspective and the wrong diagnosis may actually lead to a lower damages award and the wrong treatment. That is not to say that in an appropriate case it is the right diagnosis, but experts and practitioners must remember that not only must the criteria be present but there must also be no diagnosis which better fits the symptoms. CRPS is a diagnosis of exclusion.
In answer to the question I posed at the beginning, yes, CRPS exists but not as much as is alleged during litigation. It may once have existed, but actually no longer be CRPS. It can in an appropriate case be proven but true cases are very rare and great care must be taken.
Ruffell v Lovatt (2018) unreported, Winchester County Court, HHJ Hughes QC, 4 April.