Coarse, jerky foot tremor: Tremographic investigation of an objective sign of acute akathisia

Abstract

In a previous clinical investigation, jerky foot movements were observed in patients with akathisia. Tremographic techniques were employed in the present study to characterise this motor activity. Six psychiatric patients with signs and symptoms of akathisia, six control patients matched for antipsychotic drug dose, and five drug-free normal subjects, were selected and assessed for evidence of drug-induced movement disorders. The two patient groups proved to be closely matched on clinical and demographic variables. An accelerometer was used to record finger and toe tremor in all subjects according to a standard procedure. Analysis of the amplitude, frequency and wave-form data collected revealed that the akathisia patients were characterised by the presence of large amplitude, low frequency (less than 4 Hz), rhythmic foot movements. Changes in the severity of akathisia at follow-up were reflected in changes in the amplitude and frequency of this dyskinesia. Possible clinical and pathophysiological implications of the findings are presented.

Akathisia Masked by Hypokinesia

“…These movements typical of akathisia can be detected by EMG and their pathognomonic frequency range is 0.5 ± 3 Hz (Cunningham et al, 1996). The frequency of akathisia movements demonstrated by accelerometry is below 4 Hz, whereas the frequency of Parkinsonian tremor is higher, generally above 4 Hz, and is thus distinguishable from akathisia (Braude et al, 1984;Rapaport et al, 1994 n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n Case Report n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n 147 Received:…”

Antisocial Violent Offenders With Attention Deficit Hyperactivity Disorder Demonstrate Akathisia-Like Hyperactivity in Three-Channel Actometry

“…8,9 Reports on the movement pattern in NIA are consistent, independent of the recording method. [10][11][12] A dopaminergic deficit seems to be a common etiologic factor for these two hyperkinetic disorders. The hypodopaminergic etiology in ADHD is supported by the therapeutic effect of psychostimulants 13 and dopamine-related candidate gene findings, 14 whereas the antidopaminergic function behind akathisia has been verified by positron emission tomography.…”

Zur Symptomatologie der Akathisie

“…Neben der tardiven Dyskinesie müssen noch andere extrapyramidale Bewegungsstörungen in die Differentialdiagnose einbezogen werden: Zwar kann auch bei der Akathisie ein Tremor auftreten, dieser unterscheidet sich jedoch von dem Tremor beim Parkinson-Syndrom durch die Lokalisation an den unteren Extremitäten, die große Amplitude und die niedrige Frequenz [11]. Obwohl die Akathisie auch im Rahmen eines Parkinson-Syndroms auftreten kann, muß sie daher von diesem abgegrenzt werden [31).…”