Research Article

Experimental Brain Research

, Volume 156, Issue 2, pp 240-254

Greater impairment of extension movements as compared to flexion movements in Parkinson’s disease

  • Julie A. RobichaudAffiliated withDepartment of Human Movement Sciences (M/C 194), University of Illinois at ChicagoDepartment of Physical Therapy, University of Illinois at Chicago Email author 
  • , Kerstin D. PfannAffiliated withDepartment of Human Movement Sciences (M/C 194), University of Illinois at Chicago
  • , Cynthia L. ComellaAffiliated withDepartment of Neurological Sciences, Rush Medical Center
  • , Melanie BrandaburAffiliated withDepartment of Neurology, University of Illinois at ChicagoNPF Center of Excellence and Movement Disorders Center, Alexian Neuroscience Institute
  • , Daniel M. CorcosAffiliated withDepartment of Human Movement Sciences (M/C 194), University of Illinois at ChicagoDepartment of Physical Therapy, University of Illinois at ChicagoDepartment of Neurological Sciences, Rush Medical CenterDepartment of Bioengineering, University of Illinois at Chicago

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access

Abstract

Research on isometric contractions in subjects with Parkinson’s disease (PD) has shown that anti-parkinsonian medication results in a greater increase in extensor strength than flexor strength. This finding is consistent with the hypothesis that there is a greater impairment in neural activation of extensor muscles as compared to flexor muscles in subjects with PD. Such a hypothesis is physiologically feasible given the known differences in the neural control of flexor and extensor muscles. If the above hypothesis is true for both phasic and tonic muscle activation, then differences between performance of rapid single-joint flexion and extension movements should exist in subjects with PD. Twelve subjects with PD, “off” and “on” medication, and 12 age- and sex-matched healthy control subjects performed rapid single-joint movements in flexion and extension over three distances. For neurologically healthy subjects, we did not identify any significant differences in either kinematic or EMG parameters between flexion and extension movements. In contrast, in the PD subjects extension movements were slower and associated with more agonist bursts when compared to flexion movements. The results are consistent with the hypothesis that there is a differential impairment of neural activation of extensor muscles of the arm as compared to flexor muscles in subjects with PD.

Keywords

Parkinson’s disease Movement disorders Single-joint movements Motor control