Assessment of patients with functional neurologic disorders.

We describe an overall approach and structure to the clinical assessment of the patient with a functional neurologic disorder. Whilst the primary purpose of the assessment is to make a diagnosis and develop a treatment plan, we believe the assessment also plays a key role in treatment in its own right, as it sets a tone and context for future clinical interactions. We aim to set up an atmosphere of collaboration based on taking the patient's problems seriously, and emphasizing that all facets of the patient's presentation - physical, psychologic, and social - are of importance. Patients with functional disorders can be perceived as difficult to help and yet with the correct approaches we believe the consultation can be much more satisfying for both patient and doctor. Finally, we discuss and list some of the common diagnostic pitfalls in the assessment of functional neurologic disorders, looking at features that lead to erroneous diagnosis of neurologic disease (such as old age, la belle indifférence, and lack of psychiatric comorbidity) and an erroneous diagnosis of a functional disorder (such as "bizarre" gait in stiff-person syndrome).