Linda Rennie1, Niklas Löfgren2, Rolf Moe-Nilssen3, Arve Opheim4, Espen Dietrichs5, Erika Franzén6. 1. Sunnaas Rehabilitation Hospital, Research Department, Nesodden, Norway. Electronic address: linda.rennie@sunnaas.no. 2. Karolinska Institutet, Department of Neurobiology, Care Sciences and Society, Division of Physiotherapy, Stockholm, Sweden; Karolinska University Hospital, Function Allied Health Professionals, Function Area Occupational Therapy and Physiotherapy, Stockholm, Sweden. Electronic address: niklas.lofgren@ki.se. 3. Physiotherapy Research Group, Department of Global Public Health and Primary Health Care, University of Bergen, Bergen, Norway. Electronic address: Rolf.Moe-Nilssen@uib.no. 4. Sunnaas Rehabilitation Hospital, Research Department, Nesodden, Norway; Rehabilitation Medicine, Institute of Neuro Science and Physiology, University of Gothenburg, Gothenburg, Sweden; Habilitation & Health, Region Västra Götaland, Gothenburg, Sweden. Electronic address: Arve.Opheim@sunnaas.no. 5. Department of Neurology, Oslo University Hospital, Oslo, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway. Electronic address: espen.dietrichs@medisin.uio.no. 6. Sunnaas Rehabilitation Hospital, Research Department, Nesodden, Norway; Karolinska Institutet, Department of Neurobiology, Care Sciences and Society, Division of Physiotherapy, Stockholm, Sweden; Karolinska University Hospital, Function Allied Health Professionals, Function Area Occupational Therapy and Physiotherapy, Stockholm, Sweden. Electronic address: erika.franzen@ki.se.
Abstract
BACKGROUND: Step-to-step variability is a marker of reduced motor control and a frequently studied outcome measure in neurodegenerative disorders such as Parkinson's disease (PD) as compared to healthy older adults (HOA). To challenge motor control of gait, walking should be tested at different gait speeds. Good reliability is essential, and gait variability estimates show good reproducibility when sampled at normal gait speed. The aim was therefore to investigate if gait variability could be reliably sampled at slow and fast speeds for individuals with PD and HOA by evaluating test-retest reliability. METHODS: 29 (14 males) subjects with idiopathic PD, Hoehn &Yahr 2 (n = 18) and 3, ≥ 60 years, and 25 age matched HOAwere included. Spatiotemporal gait data was collected (GAITRite) during slow, normal, and fast walking on two occasions. RESULTS: Measurement error was lowest for gait variability estimates based on 40 steps in both groups. This was true across all speeds in HOA, but only for normal and fast gait speeds in the PD cohort. Due to increased homogeneity in the variability estimates intraclass correlation coefficients (ICC) were low for HOA, except for step width variability. In the PD cohort ICCs were good to excellent for temporal- and step width gait variability across speeds. CONCLUSION: HOA demonstrated reliable gait variability estimates across all speeds, whereas Individuals with PD were reliable at normal and fast gait speeds only Estimates should be based on at least 40 steps. Step width variability was overall the most reliable variable across groups and speed conditions.
BACKGROUND: Step-to-step variability is a marker of reduced motor control and a frequently studied outcome measure in neurodegenerative disorders such as Parkinson's disease (PD) as compared to healthy older adults (HOA). To challenge motor control of gait, walking should be tested at different gait speeds. Good reliability is essential, and gait variability estimates show good reproducibility when sampled at normal gait speed. The aim was therefore to investigate if gait variability could be reliably sampled at slow and fast speeds for individuals with PD and HOA by evaluating test-retest reliability. METHODS: 29 (14 males) subjects with idiopathic PD, Hoehn &Yahr 2 (n = 18) and 3, ≥ 60 years, and 25 age matched HOAwere included. Spatiotemporal gait data was collected (GAITRite) during slow, normal, and fast walking on two occasions. RESULTS: Measurement error was lowest for gait variability estimates based on 40 steps in both groups. This was true across all speeds in HOA, but only for normal and fast gait speeds in the PD cohort. Due to increased homogeneity in the variability estimates intraclass correlation coefficients (ICC) were low for HOA, except for step width variability. In the PD cohort ICCs were good to excellent for temporal- and step width gait variability across speeds. CONCLUSION: HOA demonstrated reliable gait variability estimates across all speeds, whereas Individuals with PD were reliable at normal and fast gait speeds only Estimates should be based on at least 40 steps. Step width variability was overall the most reliable variable across groups and speed conditions.
Authors: Vrutangkumar V Shah; James McNames; Graham Harker; Martina Mancini; Patricia Carlson-Kuhta; John G Nutt; Mahmoud El-Gohary; Carolin Curtze; Fay B Horak Journal: Sensors (Basel) Date: 2020-10-12 Impact factor: 3.576