Functional Neurological Disorder: Finding order within the disorder

Weightmans recently hosted another of its flagship monthly catastrophic injury training sessions, presented by Neil Block QC, Head of 39 Essex Chambers, entitled ‘Functional Neurological Disorder — is it all in the head?’.

Functional Neurological Disorder (“FND”) is a medical condition in which the brain and body do not communicate as they should. It is experienced as a dysfunction of the nervous system, but it is not caused by any physical neurological impairment.

Common symptoms of FND include paralysis, weakness, abnormalities of movement, sensory dysfunction, seizures and cognitive difficulties. FND may be a stand-alone diagnosis (for example, in an individual with no neurological compromise whatsoever) or it can be comorbid with symptoms emanating from an injury with an identifiable physical pathology, for example where a physical injury can account for some level of symptoms but not the full extent of the presentation.

A claimant with a spinal cord injury presenting with symptoms consistent with his/her underlying neurological pathology poses no great challenge to experienced personal injury practitioners. However, a claimant reporting muscle weakness, abnormal gait, sensory impairment and seizures where such symptoms are wholly inconsistent with the underlying physical condition will likely generate highly contentious litigation. A claim relating to an injury that initially appeared relatively innocuous can, where FND is a factor, take an unexpected and dramatic turn. It is therefore vital to recognise when FND is a factor in a claim at the earliest practicable opportunity. FND can give rise to significantly disabling symptoms over many months and years and claims can potentially be very expensive.

Faced with a claimant presenting unexplained neurological symptoms, it is essential to assemble a compelling and robust consensus of expert medical opinion. Experts with specialist knowledge and experience of FND in a medico-legal context are absolutely key to achieving an optimum outcome. In most cases, this will require:

• A consultant neurologist. They will identify the extent of the explicable neurological deficits (if any) and will be able to distinguish those symptoms which are disproportionate or wholly inexplicable on the basis of the underlying neurological pathology
• A consultant neuropsychiatrist/psychiatrist. This will be the lead expert in most FND cases and will likely make the diagnosis of FND or otherwise refute the diagnosis if they believe there is an alternative, preferred diagnosis. In cases where the diagnosis of FND is not, of itself a contentious issue, the neuropsychiatrist/psychiatrist’s opinion on causation and the ‘but for’ scenario will be fundamental to the outcome of the claim
• In cases involving soft tissue or bony injury, a consultant orthopaedic surgeon may need to identify the extent to which the injury could give rise to features such as reduced range of movement or weakness. They will distinguish the ‘in-scope’ symptoms from those that cannot be explained on an orthopaedic basis
• In cases involving a head injury, a consultant neuropsychologist will address the cognitive symptoms arising from, and attributable to, the injury. Again, symptoms that are considered disproportionate will then require an explanation from another expert (i.e. the neuropsychiatrist). Neuropsychological testing, including robust performance validity testing, can help identify genuinely reported deficits.

The inherent nature of FND claims means that it can be difficult to completely dispel suspicions of malingering, even when the experts agree that a valid FND diagnosis can be made. Surveillance will often be a useful tool to gain further insight into the claimant’s presentation but be warned: FND symptoms are by their very nature variable and inconsistent and surveillance footage needs to be considered very carefully. There is also a human factor to bear in mind: individuals who develop FND often have complex medical and psychosocial histories and casting doubt on their veracity can be like detonating a hand grenade. Deploying the right evidence at the right time can be the difference between defeating the claim or inflating it.

Weightmans plans to host a round table discussion with leading individuals from the insurance and legal industries to share experiences with regard to identifying cases, use of experts and best practices on how to settle what can be extremely difficult and expensive cases. 

Register your interest to attend the event by filling in the form below