[Functional neurological disorders and forensic medicine: Clinical and practical characteristics]

Functional neurological disorders (FND) have long been a challenge for medicine, both on clinical and psychodynamic point of view. The medico-legal issue is often relegated to the background in medicine, and FND patients also suffer from such neglected topic. Nonetheless, despite the difficulty to properly diagnose FND and the numerous associated organic and/or psychiatric comorbidities, FND patients report a significant level of deficiency and a high alteration of quality of life when compared to other well-recognized chronic disorders such as Parkinson's disease or epilepsy. Whether it is for the estimation of a personal injury, a prejudice, after-effects following a medical accident or certain legal contexts requiring the elimination of a factitious disorder or a simulation, the uncertainty and imprecision in the medico-legal assessment can imply notable consequences on the patient. In this article, we propose to define the different medico-legal contexts in which FND can occur that of the legal expert, that of the consulting physician, that of the so-called recourse physician and finally that of the attending physician who can provide detailed medical files to the patient in order to help him/her in his/her procedures. We then explain how to use standardized objective evaluation tools validated by the learned societies and how to encourage multidisciplinary cross-evaluation. Finally, we specify how to differentiate FND from historically FND-associated disorders (factitious and simulated disorders), through the clinical criteria, considering the difficulties linked to the uncertainty in the clinical examination of these disorders in a medico-legal context. In addition to the rigorous completion of expertise missions, we aim to reduce two damaging consequences characterizing FND: diagnostic delay and the patients' suffering through stigma.