[Functional neurological disorders and forensic medicine: Clinical and practical characteristics]. / Troubles neurologiques fonctionnels et expertise médico-légale : aspects cliniques et pratiques.

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.

[Diagnostic criteria, epidemiology and assessment of patients with functional neurological disorders]. / Définitions, épidémiologie et démarche diagnostique clinique dans les troubles neurologiques fonctionnels.

Functional neurological disorders (FND) are symptoms that can affect a variety of functions including motor, sensory and cognitive. These symptoms are genuinely experienced by the patient and are related to a functional disorder rather than a structural one. There is little epidemiological data on these disorders, but their frequency is well established in clinical practice, it is the second most frequent reason for consultation in Neurology. Despite of the frequency of the disorder, general practitioners and specialists are insufficiently trained in the disease, and patients often suffer from stigmatization and/or unnecessary investigations. It is therefore important to be aware of the diagnostic approach to FND, which mostly relies on positive clinical signs. Psychiatric evaluation can help with the characterization of predisposing, precipitating and perpetuating factors of the symptoms (according to the 3P biopsychosocial model related to FND), and guide their management. Finally, diagnosis explanation is a crucial step in the management of the disease, which can in itself have a therapeutic effect, and allow the patient to adhere to the treatments.

Overall comorbidities in functional neurological disorder: A narrative review.

INTRODUCTION: The importance to assess and include the frequent comorbidities in the personalised care management plan of patients with functional neurological disorders (FND) has arisen through the years. FND patients are not only complaining from motor and/or sensory symptoms. They also report some non-specific symptoms that participate to the burden of FND. In this narrative review, we aim to better describe these comorbidities in terms of prevalence, clinical characteristics and their variability depending on the subtype of FND. METHODS: The literature was searched for on Medline and PubMed. The search was narrowed to articles between 2000 and 2022. RESULTS: Fatigue is the most common symptom reported in relation to FND (from 47 to 93%), followed by cognitive symptoms (from 80 to 85%). Psychiatric disorders are reported in 40 to 100% FND patients, depending on the FND subtype (functional motor disorder [FMD], functional dissociative seizures [FDS]…) but also on the type of psychiatric disorder (anxiety disorders being the most frequent, followed by mood disorders and neurodevelopmental disorders). Stress factors such as childhood trauma exposure (emotional neglect and physical abuse predominantly) have also been identified in up to 75% of FND patients, along with maladaptive coping strategies. Organic disorders are commonly reported in FND, such as neurological disorders (including epilepsy in FDS [20%] and FMD in Parkinson's Disease [7%]). Somatic symptom disorders including chronic pain syndromes are frequently associated to FND (about 50%). To be noted, recent data also suggest a high comorbidity between FND and hypermobile Ehlers Danlos Syndrome (about 55%). CONCLUSION: Put together, this narrative review highlights the high burden of FND patients, not only due to somatosensory alterations but also by considering the frequent comorbidities reported. Thus, such comorbidities must be taken into consideration when defining the FND personalised care management strategy for the patients.

[Overview of care management principles in functional neurological disorders]. / Synthèse des principes et schémas de prise en charge dans les troubles neurologiques fonctionnels.

After more than twenty years of academic research on functional neurological disorders (FND) throughout the world, a standardized care management strategy has emerged to allow a more adapted care offer to patients with FND, as close as possible to their experience and their needs. With regard to this special issue on FND in collaboration with L'Encéphale and at the initiative of the Neuropsychiatry section of the AFPBN (French Association of Biological Psychiatry and Neuropsychopharmacology), we would like to suggest a summary of all topics discussed in more detail in each article of this special issue, in order to facilitate its reading. We therefore cover the following themes: the initial contact with a patient with FND, the diagnostic process in favor of a positive diagnosis, the physiological, neural and psychological basis of FND, the diagnostic announcement (and its intangibles), the therapeutic patient education in FND, the general principles of therapeutic management through a personalized and multidisciplinary care program, and the validated therapeutic tools available according to the symptoms identified. This article is designed to be of broad interest on FND, supported by tables and figures showing the key points of all these steps, to keep an educational purpose at most. We hope that through this special issue, each health professional will be able to grasp this knowledge and this framework of care as easily and quickly as possible, in order to participate in the standardization of the care offer.

[Functional neurological disorders: A clinical anthology]. / Troubles neurologiques fonctionnels : une anthologie clinique.

Functional neurological disorders have a broad phenotypic spectrum and include different clinical syndromes, which are sometimes associated to each other or appear consecutively over the course of the disease. This clinical anthology provides details on the specific and sensitive positive signs that are to be sought in the context of a suspected functional neurological disorder. Beside these positive elements leading to the diagnosis of functional neurological disorder, we should keep in mind the possibility of an associated organic disorder as the combination of both organic and functional disorders is a relatively frequent situation in clinical practice. Here we describe the clinical characteristics of different functional neurological syndromes: motor deficits, abnormal hyperkinetic and hypokinetic movements, voice or speech disorders, sensory disorders, and functional dissociative seizures. The clinical examination and the identification of positive signs play a critical role in the diagnosis of functional neurological disorder. Knowledge of the specific signs associated with each phenotype render possible to make an early diagnosis. For that matter, it contributes to the improvement of patient care management. It allows to a better engagement in an appropriate care pathway, which influence their prognosis. Highlighting and discussing positive signs with patients can also be an interesting step in the process of explaining the disease and its management.

[Validated care programs for patients with functional neurological disorders]. / Modèles de soins validés pour les patients souffrant de troubles neurologiques fonctionnels.

Functional neurological disorder (FND) is a common cause of persistent and disabling neurological symptoms. Diagnostic delay may lead to no treatment, inappropriate treatment or even iatrogenic symptoms. Yet, several treatments significantly reduce physical symptoms and improve functioning in FND patients even though not all patients respond to the currently available treatments. This review aims to describe the range of evidence-based rehabilitative and/or psychological therapeutic approaches available for FND patients. The most effective treatments are multidisciplinary and coordinated; using an outpatient or inpatient setting. Building a network of FND-trained healthcare professionals around the patient is an essential aspect of optimal patient management. Indeed, a supportive environment coupled with a collaborative therapeutic relationship improves understanding of FND and appears to help patients engage in appropriate treatments. Patients need to be invested in their own care and have to understand that recovery may depend on their commitment. The conventional treatment combines psychoeducation, physical rehabilitation and psychotherapy (cognitive and behavioral therapy, hypnosis, psychodynamic interpersonal therapy). Early referral of patients to physical therapy is recommended; however, the optimal parameters of treatment, duration and intensity are unknown and seem to vary with the severity and chronicity of symptoms. The goal is to minimize self-awareness by diverting attention or by stimulating automatically generated movements with non-specific and gradual exercises. The use of compensatory technical aids should be avoided as much as possible. Psychotherapeutic management should encourage self-evaluation of cognitive distortions, emotional reactions and maladaptive behaviors while empowering the patient in managing symptoms. Symptom management can use anchoring strategies to fight against dissociation. The aim is to connect to the immediate environment and to enrich one's sensoriality. The psychological interventions should then be adapted to the individual psychopathology, cognitive style and personality functioning of each patient. There is currently no known curative pharmacological treatment for FND. The pharmacological approach rather consists of progressively discontinuing medication that was introduced by default and that could lead to undesirable side effects. Finally, neurostimulation (transcranial magnetic stimulation, transcranial direct current stimulation) can be effective on motor FND.

[Understanding functional neurological disorders: From biological markers to pathophysiological models]. / Étiopathogénie des troubles neurologiques fonctionnels : marqueurs biologiques et modèles théoriques.

OBJECTIVES: Functional neurological disorders have witnessed intense research activity in the fields of structural and functional neuroimaging for more than twenty years. Thus, we propose a synthesis of recent research findings and etiological hypotheses that have been proposed so far. This work should help clinicians to better understand the nature of the mechanisms involved, but also help patients to increase their knowledge about the biological features underlying their functional symptoms. METHODS: We carried out a narrative review of international publications dealing with neuroimaging and biology of functional neurological disorders, from 1997 to 2023. RESULTS: Several brain networks underlie functional neurological symptoms. These networks play a role in the management of cognitive resources, in attentional control, emotion regulation, in agency and in the processing of interoceptive signals. The mechanisms of the stress response are also associated with the symptoms. The biopsychosocial model helps to better understand predisposing, precipitating, and perpetuating factors involved. The functional neurological phenotype results from the interaction between: i) a specific pre-existing vulnerability resulting from biological background and epigenetic modifications, and ii) exposure to stress factors, according to the stress-diathesis model. This interaction causes emotional disturbances including hypervigilance, lack of integration of sensations and affects, and emotional dysregulation. These characteristics in turn impact the cognitive, motor and affective control processes related with the functional neurological symptoms. CONCLUSIONS: A better knowledge of the biopsychosocial determinants of brain network dysfunctions is necessary. Understanding them would help developing targeted treatments, but is also critical for patients care.