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CNS Drugs

, Volume 27, Issue 2, pp 97–112 | Cite as

Postural Instability in Patients with Parkinson’s Disease

Epidemiology, Pathophysiology and Management
  • Samuel D. Kim
  • Natalie E. Allen
  • Colleen G. Canning
  • Victor S. C. Fung
Review Article

Abstract

Postural instability is one of the cardinal signs in Parkinson’s disease (PD). It can be present even at diagnosis, but becomes more prevalent and worsens with disease progression. It represents one of the most disabling symptoms in the advanced stages of the disease, as it is associated with increased falls and loss of independence. Clinical and posturographic studies have contributed to significant advances in unravelling the complex pathophysiology of postural instability in patients with PD, but it still remains yet to be fully clarified, partly due to the difficulty in distinguishing between the disease process and the compensatory mechanisms, but also due to the fact that non-standardized techniques are used to measure balance and postural instability. There is increasing evidence that physical therapy, especially highly challenging balance exercises, can improve postural stability and reduce the risk of falls, although the long-term effects of physical therapy interventions on postural stability need to be explored given the progressive nature of PD. Pharmacotherapy with dopaminergic medications can provide significant improvements in postural instability in early- to mid-stage PD but the effects tend to wane with time consistent with spread of the disease process to non-dopaminergic pathways in advanced PD. Donepezil has been associated with a reduced risk of falls and methylphenidate has shown potential benefit against freezing of gait, but the results are yet to be replicated in large randomized studies. Surgical treatments, including lesioning and deep brain stimulation surgery targeting the subthalamic nucleus and the globus pallidus internus, tend to only provide modest benefit for postural instability. New surgical targets such as the pedunculopontine nucleus have emerged as a potential specific therapy for postural instability and gait disorder but remain experimental.

Keywords

Levodopa Deep Brain Stimulation Postural Instability Rasagiline Gait Disorder 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgments

No funding was provided for the preparation of the paper. There were no conflicts of interest for all authors. No other persons other than those listed as authors contributed to the work.

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Copyright information

© Springer International Publishing Switzerland 2012

Authors and Affiliations

  • Samuel D. Kim
    • 1
    • 2
  • Natalie E. Allen
    • 3
  • Colleen G. Canning
    • 3
  • Victor S. C. Fung
    • 1
    • 2
  1. 1.Movement Disorders Unit, Department of NeurologyWestmead HospitalWestmeadAustralia
  2. 2.Sydney Medical School-Western, The University of SydneySydneyAustralia
  3. 3.Clinical and Rehabilitation Sciences Research Group, Faculty of Health SciencesThe University of SydneySydneyAustralia

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