Related Experiment Video
Updated: Jan 27, 2026

An Instrumented Pull Test to Characterize Postural Responses
Published on: April 6, 2019
How Do I Test for Postural Stability?
Christopher G Goetz1, Padmaja Vittal1, John Maldonado1
1Rush University Medical Center Chicago Illinois USA.
Abstract:
One of the core elements of Parkinson's disease is postural reflex compromise. To test postural stability, the International Parkinson and Movement Disorder Society revision of the UPDRS (MDS-UPDRS) provides very specific instructions for uniform and safe testing. Item 3.12 (postural stability) is assessed after properly positioning the subject and explaining the testing procedure. After, the rater pulls briskly on the shoulders so that the subject must step backward and attempt to stabilize without falling. Based on the stability response, the rater enters the appropriate integer (0, 1, 2, 3, or 4) using the descriptive anchors for this item from the overall scale. With following proper safety measures and guidelines, all raters can perform this testing maneuver.
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