title: Functional limb weakness and paralysis.
abstract: Functional (psychogenic) limb weakness describes genuinely experienced limb power or paralysis in the absence of neurologic disease. The hallmark of functional limb weakness is the presence of internal inconsistency revealing a pattern of symptoms governed by abnormally focused attention. In this chapter we review the history and epidemiology of this clinical presentation as well as its subjective experience highlighting the detailed descriptions of authors at the end of the 19th and early 20th century. We discuss the relevance that physiological triggers such as injury and migraine and psychophysiological events such as panic and dissociation have to understanding of mechanism and treatment. We review many different positive diagnostic features, their basis in neurophysiological testing and present data on sensitivity and specificity. Diagnostic bedside tests with the most evidence are Hoover's sign, the hip abductor sign, drift without pronation, dragging gait, give way weakness and co-contraction.
authors.affiliation: Department of Clinical Neurosciences, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK. Electronic address: jon.stone@ed.ac.uk.
authors.forename: J
authors.initials: J
authors.lastname: Stone
authors.affiliation: Neurology Service, Geneva University Hospitals and Laboratory for Behavioural Neurology and Imaging of Cognition, University of Geneva-Campus Biotech, Geneva, Switzerland.
authors.forename: S
authors.initials: S
authors.lastname: Aybek
mesh_terms: D003291:Conversion Disorder / Q000266:history*; D049668:History, 15th Century; D049669:History, 16th Century; D049670:History, 17th Century; D049671:History, 18th Century; D049672:History, 19th Century; D049673:History, 20th Century; D049674:History, 21st Century; D049691:History, Medieval; D006801:Humans; D018908:Muscle Weakness / Q000266:history* / Q000523:psychology; D009422:Nervous System Diseases / Q000266:history* / Q000523:psychology*; D010243:Paralysis / Q000266:history* / Q000523:psychology
keywords: conversion disorder; functional neurologic symptoms; limb weakness; nonorganic; paralysis; paresis; psychogenic