Parkinson’s Disease: Hoehn and Yahr Scale

The Hoehn and Yahr scale (HY) is a widely used clinical rating scale, which defines broad categories of motor function in Parkinson’s disease (PD). Among its advantages are that it is simple and easily applied. It captures typical patterns of progressive motor impairment which can be applied whether or not patients are receiving dopaminergic therapy. Progression in HY stages has been found to correlate with motor decline, deterioration in quality of life, and neuroimaging studies of dopaminergic loss. However, because of its simplicity and lack of detail, the scale is not comprehensive. It is also limited by its focus on issues of unilateral versus bilateral disease and the presence or absence of postural reflex impairment, thereby leaving other specific aspects of motor deficit unassessed.

Authors and Affiliations

1. Chulalongkorn Center of Excellence on Parkinson’s Disease and Related Disorders, Chulalongkorn University Hospital, Bangkok, Thailand

   Roongroj Bhidayasiri MD, FRCP, FRCPI

2. Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA

   Roongroj Bhidayasiri MD, FRCP, FRCPI

3. Department of Neurology, Harvard Medical School Beth Israel Deaconess Medical Center, Boston, MA, USA

   Daniel Tarsy MD

Reprints and permissions

© 2012 Springer Science+Business Media New York

Policies and ethics