TY - GEN
T1 - Analyzing 180° turns using an inertial system reveals early signs of progression of Parkinson's disease
AU - Salarian, Arash
AU - Zampieri, Cris
AU - Horak, Fay B.
AU - Carlson-Kuhta, Patricia
AU - Nutt, John G.
AU - Aminian, Kamiar
PY - 2009
Y1 - 2009
N2 - Changes in turning are one of the early motor deficiencies in Parkinson's Disease (PD). We have proposed a system based on wearable, inertial sensors and a novel automatic analysis algorithm that can assess 180° turns. Twelve patients in early stages of PD and 14 age-matched healthy subjects were enrolled in this study. Inertial sensors were attached on shanks and sternum. Measurement protocol included walking on a straight pathway, turning 180° and returning back. Subjects were measured 4 times, once every 6 months during an 18 months period. At the baseline, 9 subjects from each group repeated the test twice to assess test-retest reliability. Patients with mild PD had a very low Postural Instability Gait Difficulty (PIGD subscore of UPDRS III) score (average 0.67, min 0, max 3). The analysis showed that the patients had a significantly longer turning duration (2.18±0.43 vs. 1.79±0.27 seconds, p<0.02) and longer delay in their last step before initiating a turn (0.56±0.04 vs. 0.52±0.04 seconds, p<0.03). Estimated turning duration and other metrics had a high test-retest reliability (ρ>0.85). Turning duration also showed a significant Group*Time interaction (p<0.03) during the longitudinal study highlighting early signs of the progression of the disease.
AB - Changes in turning are one of the early motor deficiencies in Parkinson's Disease (PD). We have proposed a system based on wearable, inertial sensors and a novel automatic analysis algorithm that can assess 180° turns. Twelve patients in early stages of PD and 14 age-matched healthy subjects were enrolled in this study. Inertial sensors were attached on shanks and sternum. Measurement protocol included walking on a straight pathway, turning 180° and returning back. Subjects were measured 4 times, once every 6 months during an 18 months period. At the baseline, 9 subjects from each group repeated the test twice to assess test-retest reliability. Patients with mild PD had a very low Postural Instability Gait Difficulty (PIGD subscore of UPDRS III) score (average 0.67, min 0, max 3). The analysis showed that the patients had a significantly longer turning duration (2.18±0.43 vs. 1.79±0.27 seconds, p<0.02) and longer delay in their last step before initiating a turn (0.56±0.04 vs. 0.52±0.04 seconds, p<0.03). Estimated turning duration and other metrics had a high test-retest reliability (ρ>0.85). Turning duration also showed a significant Group*Time interaction (p<0.03) during the longitudinal study highlighting early signs of the progression of the disease.
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U2 - 10.1109/IEMBS.2009.5333970
DO - 10.1109/IEMBS.2009.5333970
M3 - Conference contribution
C2 - 19964471
AN - SCOPUS:84903864669
SN - 9781424432967
T3 - Proceedings of the 31st Annual International Conference of the IEEE Engineering in Medicine and Biology Society: Engineering the Future of Biomedicine, EMBC 2009
SP - 224
EP - 227
BT - Proceedings of the 31st Annual International Conference of the IEEE Engineering in Medicine and Biology Society
T2 - 31st Annual International Conference of the IEEE Engineering in Medicine and Biology Society: Engineering the Future of Biomedicine, EMBC 2009
Y2 - 2 September 2009 through 6 September 2009
ER -