Article Text

PDF

Measurement of involuntary arm movement in athetotic patients
  1. Peter D. Neilson1
  1. Division of Neurology, The Prince Henry Hospital, Sydney, Australia
  2. The Schools of Medicine and Physics, University of New South Wales, Sydney, Australia

    Abstract

    Visual tracking tests have been used to obtain a quantified statistical description of the involuntary movements of the arm about the elbow joint in a group of patients suffering from athetoid cerebral palsy. Three separate components of involuntary activity can be recognized and it is possible that each may be a different physiological mechanism. First there are irregular movements which are represented by a continuous power spectrum which decreases with increasing frequency, reaching a negligible value between 2-3 Hz. The second component is a rhythmical low frequency movement which is indicated by a predominant peak in the power spectrum at a frequency of 0·3-0·6 Hz. The presence of this peak was predicted in a previous paper because of underdamping demonstrated in the closed loop voluntary control of movement in athetosis. The third component is the athetoid action tremor in which both agonist and antagonist muscle groups contract vigorously but asynchronously at a frequency of 1·5-4 Hz.

    Statistics from Altmetric.com

    Footnotes

    • 1 Address for reprints: Clinical Sciences Building, The Prince Henry Hospital, Little Bay, N.S.W., Australia.

    Request permissions

    If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.