Research Article| Volume 334, ISSUE 1-2, P14-17, November 15, 2013

Objectification of psychogenic postural instability by trunk sway analysis

Published:August 09, 2013DOI:



      The attribution of balance or gait disorders to psychogenic origin can be exceedingly challenging, as clinical tests involving distraction maneuvers are prone to subjective bias. We tested the value of biomechanical balance analysis to identify psychogenic balance and gait (PBG) disorders. Methods: We quantified and compared the effects of distraction maneuvers on balance based on four stance conditions (eyes open, EO; eyes closed, EC; EO on foam, EOF; and EC on foam; ECF) in subjects with suspected PBG (n = 12), subjects with balance and gait disorder due to multiple sclerosis (MS; n = 12) and healthy controls (n = 12). We measured trunk inclination in transverse plane (°)2 and the corresponding body angular velocity (°/s). Distractibility of postural stability was analysed using ANOVA with repeated measures.


      In evident contrast to the MS group and healthy controls, the PBG group showed increased values of (°)2 and (°/s) and significant distractibility in all four stance conditions.


      Biomechanical balance analysis can help clinicians to get objective, quantified results of distraction maneuvers and confirm a positive diagnosis of PBG disorders. Large prospective studies are needed to confirm these results.


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        • Keane J.R.
        Hysterical gait disorders.
        Neurology. 1989; 39: 586-589
        • Kanaan R.
        • Armstrong D.
        • Barnes P.
        • Wessely S.
        In the psychiatrist’s chair: how neurologists understand conversion disorder.
        Brain. 2009; 132: 2889-2896
        • Crimlisk H.L.
        • Bhatia K.
        • Cope H.
        • David A.
        • Marsden C.D.
        • Ron M.A.
        Slater revisited: 6 year follow up study of patients with medically unexplained motor symptoms.
        BMJ. 1998; 316: 582-586
        • Feinstein A.
        • Stergiopoulos V.
        • Fine J.
        • Lang A.E.
        Psychiatric outcome in patients with a psychogenic movement disorder: a prospective study.
        Neuropsychiatry Neuropsychol Behav Neurol. 2001; 14: 169-176
        • Stone J.
        • Carson A.
        • Sharpe M.
        Functional symptoms and signs in neurology: assessment and diagnosis.
        J Neurol Neurosurg Psychiatry. 2005; 76: i2-i12
        • Lempert T.
        • Brandt T.
        • Dieterich M.
        • Huppert D.
        How to identify psychogenic disorders of stance and gait. A video study in 37 patients.
        J Neurol. 1991; 238: 140-146
        • Madhusudanan M.
        Psychiatric symptoms in neurological practice.
        Ann Indian Acad Neurol. 2006; 9: 72-89
        • Jordbru A.A.
        • Smedstad L.M.
        • Moen V.P.
        • Martinsen E.W.
        Identifying patterns of psychogenic gait by video-recording.
        J Rehabil Med. 2012; 44: 31-35
        • Williams D.T.
        • Ford B.
        • Fahn S.
        Phenomenology and psychopathology related to psychogenic movement disorders.
        Adv Neurol. 1995; 65: 231-257
        • Voon V.
        • Lang A.E.
        • Hallett M.
        Diagnosing psychogenic movement disorders: which criteria should be used in clinical practice?.
        Nat Clin Pract Neurol. 2007; 3: 134-135
        • Gupta A.
        • Lang A.E.
        Psychogenic movement disorders.
        Curr Opin Neurol. 2009; 22: 430-436
        • Shill H.
        • Gerber P.
        Evaluation of clinical diagnostic criteria for psychogenic movement disorders.
        Mov Disord. 2006; 21: 1163-1168
        • Zeuner K.E.
        • Shoge R.O.
        • Goldstein S.R.
        • Dambrosia J.M.
        • Hallett M.
        Accelerometry to distinguish psychogenic from essential or parkinsonian tremor.
        Neurology. 2003; 61: 548-550
        • Piboolnurak P.
        • Rothey N.
        • Ahmed A.
        • Ford B.
        • Yu Q.
        • Xu D.
        • et al.
        Psychogenic tremor disorders identified using tree-based statistical algorithms and quantitative tremor analysis.
        Mov Disord. 2005; 20: 1543-1549
        • Schwingenschuh P.
        • Katschnig P.
        • Seiler S.
        • Saifee T.A.
        • Aguirregomozcorta M.
        • Cordivari C.
        • et al.
        Moving toward "laboratory-supported" criteria for psychogenic tremor.
        Mov Disord. 2011; 26: 2509-2515
        • Kang S.Y.
        • Sohn Y.H.
        Electromyography patterns of propriospinal myoclonus can be mimicked voluntarily.
        Mov Disord. 2006; 21: 1241-1244
        • Esposito M.
        • Edwards M.J.
        • Bhatia K.P.
        • Brown P.
        • Cordivari C.
        Idiopathic spinal myoclonus: a clinical and neurophysiological assessment of a movement disorder of uncertain origin.
        Mov Disord. 2009; 24: 2344-2349
        • Van der Salm S.M.
        • Koelman J.H.
        • Henneke S.
        • van Rootselaar A.F.
        • Tijssen M.A.
        Axial jerks: a clinical spectrum ranging from propriospinal to psychogenic myoclonus.
        J Neurol. 2010; 257: 1349-1355
        • Cohen L.G.
        • Hallett M.
        Hand cramps: clinical features and electromyographic patterns in a focal dystonia.
        Neurology. 1988; 38: 1005-1012
        • Malfait N.
        • Sanger T.D.
        Does dystonia always include co-contraction? A study of unconstrained reaching in children with primary and secondary dystonia.
        Exp Brain Res. 2007; 176: 206-216
        • Quartarone A.
        • Rizzo V.
        • Terranova C.
        • Morgante F.
        • Schneider S.
        • Ibrahim N.
        • et al.
        Abnormal sensorimotor plasticity in organic but not in psychogenic dystonia.
        Brain. 2009; 132: 2871-2877
        • Allum J.M.
        • Honegger F.
        • Huwiler M.
        Differential diagnosis of organic and psychogenic vertigo using dynamic posturography.
        in: Przuntek H. Kraus P.H. Klotz P. Korczyn A.D. Instrumental methods and scoring in extrapyramidal disorders. Springer, Berlin; Heidelberg; New York; Barcelona; Budapest; Hong Kong; London; Milan; Paris; Tokyo1995: 130-142
        • Goebel J.A.
        • Sataloff R.T.
        • Hanson J.M.
        • Nashner L.M.
        • Hirshout D.S.
        • Sokolow C.C.
        Posturographic evidence of nonorganic sway patterns in normal subjects, patients, and suspected malingerers.
        Otolaryngol Head Neck Surg. 1997; 117: 293-302
        • Mantu M.U.
        Discrepancy between dysmetric centrifugal movements and normometric centripetal movements in psychogenic ataxia.
        Eur Neurol. 2001; 45: 261-265
        • Hallett M.
        Physiology of psychogenic movement disorders.
        J Clin Neurosci. 2010; 17: 959-965
        • Van de Warrenburg B.P.
        • Bakker M.
        • Kremer B.P.
        • Bloem B.R.
        • Allum J.H.
        Trunk sway in patients with spinocerebellar ataxia.
        Mov Disord. 2005; 20: 1006-1013
        • Corporaal S.H.
        • Gensicke H.
        • Kuhle J.
        • Kappos L.
        • Allum J.H.
        • Yaldizli Ö.
        Balance control in multiple sclerosis: correlations of trunk sway during stance and gait tests with disease severity.
        Gait Posture. 2013; 37: 55-60
        • Factor S.A.
        • Podskalny G.D.
        • Molho E.S.
        Psychogenic movement disorders: frequency, clinical profile, and characteristics.
        J Neurol Neurosurg Psychiatry. 1995; 59: 406-412
        • Stone J.
        • Edwards M.
        Trick or treat? Showing patients with functional (psychogenic) motor symptoms their physical signs.
        Neurology. 2012; 79: 282-284
        • Hallett M.
        • Weiner W.J.
        • Kompoliti K.
        Psychogenic movement disorders.
        Parkinsonism Relat Disord. 2012; 18: S155-S157
        • Okun M.S.
        • Rodriguez R.L.
        • Foote K.G.
        • Fernandez H.H.
        The “Chair Test” to aid in the diagnosis of psychogenic gait disorders.
        Neurologist. 2007; 13: 87-91