The instrumented timed up and go test: potential outcome measure for disease modifying therapies in Parkinson's disease
- Cris Zampieri1,
- Arash Salarian1,3,
- Patricia Carlson-Kuhta1,
- Kamiar Aminian3,
- John G Nutt1,2,
- Fay B Horak1,2
- 1Balance Disorders Laboratory, Department of Neurology, School of Medicine, Oregon Health & Science University, Portland, Oregon, USA
- 2Balance Disorders Laboratory, Department of Physiology and Pharmacology, School of Medicine, Oregon Health & Science University, Portland, Oregon, USA
- 3Laboratory of Movement Analysis and Measurement, Ecole Polytechnique Fédéral de Lausanne, Lausanne, Switzerland
- Correspondence to Dr Patricia Carlson-Kuhta, Oregon Health & Science University, Department of Neurology, 505 NW 185th Avenue, Portland, OR 97006 USA;
- Received 28 January 2009
- Revised 22 June 2009
- Accepted 19 July 2009
- Published Online First 2 September 2009
The Timed Up and Go (TUG) test has been used to assess balance and mobility in Parkinson's Disease (PD). However, it is not known if this test is sensitive to subtle abnormalities present in early stages of the disease, when balance and gait problems are not clinically evident but may be detected with instrumented analysis of movement. We hypothesise that postural transitions and arm swing during gait will be the most sensitive characteristics of the TUG for early PD. In the present study, we instrumented the TUG test (iTUG) using portable inertial sensors, and extended the walking distance from 3 m (traditional TUG) to 7 m. Twelve subjects with early-to-moderate, untreated PD and 12 healthy individuals participated. Our findings show that although the stopwatch measure of TUG duration did not detect any abnormalities in early-to-mid-stage PD, the peak arm swing velocity on the more affected side, average turning velocity, cadence and peak trunk rotation velocity were significantly slower. These iTUG parameters were also correlated with the Unified Parkinson's Disease Rating Motor Scale. Thus, the iTUG test is sensitive to untreated PD and could potentially detect progression of PD and response to symptomatic and disease-modifying treatments.
Funding NIH, 9000 Rockville Pike, Bethesda, Maryland 20892, USA; Kinetics Foundation,1 First Street, Suite 12, Los Altos, CA 94022, USA.
Competing interests FBH was a consultant for Kinetics Foundation, who partially funded this study. The potential conflict of interest has been reviewed and managed by OHSU.
Ethics approval Ethics approval was provided by the Oregon Health & Science University Institutional Review Board.
Patient consent Obtained.
Provenance and peer review Not commissioned; externally peer reviewed.