title: Pre- and unplanned walking turns in Parkinson's disease - Effects of dopaminergic medication.
abstract: Although dopaminergic medication improves functional mobility in individuals with Parkinson's disease (PD), its effects on walking turns are uncertain. Our goals was to determine whether dopaminergic medication improves preplanned and unplanned walking turns in individuals with PD, compared to healthy controls. Nineteen older adults with mild-to-moderate PD and 17 healthy controls performed one of the following three tasks, presented randomly: walking straight, or walking and turning 180° to the right or left. The walking direction was visually cued before starting to walk (preplanned) or after (unplanned, i.e., 0.6m before reaching the turning point). Subjects with PD were assessed off dopaminergic medication (OFF) and on dopaminergic medication (ON) medication. Turning strategy (step and spin turns), turning performance (turning distance and body rotation) and walking pattern were analyzed for three turning steps. Irrespective of medication state and turning condition, step and spin turns followed a nearly 50:50 distribution. After intake of dopaminergic medication, subjects with PD increased their turning distance but not the amount of body rotation or their walking pattern. Compared to controls, turning impairments in subjects with PD remained while ON medication and problems regulating step width were the most prominent features of their walking pattern. Specifically, subjects with PD turned with narrower cross-over steps, i.e. when the external foot crossed over the line of progression of the internal leg. We conclude that turning impairments remained even after dopaminergic medication and problems modulating step width appears to be a critical feature for turning in PD.
authors.affiliation: Department of Neurobiology, Care Sciences and Society, Division of Physiotherapy, Karolinska Institutet, Alfred Nobels Alle 23, 141 83 Huddinge, Sweden; Functional Area Occupational Therapy & Physiotherapy, Allied Health Professionals Function, Karolinska University Hospital, Stockholm, Sweden. Electronic address: David.conradsson.1@ki.se.
authors.forename: David
authors.initials: D
authors.lastname: Conradsson
authors.affiliation: Department of Kinesiology and Physical Education, McGill University, and Interdisciplinary Research Center in Rehabilitation (CRIR), 475 Pine Avenue West, Montreal, Quebec H2W 1S4, Canada. Electronic address: Caroline.paquette@mcgill.ca.
authors.forename: Caroline
authors.initials: C
authors.lastname: Paquette
authors.affiliation: Department of Neurobiology, Care Sciences and Society, Division of Clinical Geriatrics, Novum Pl 5, Blickagången 6/Hälsovägen 7 14157 Huddinge, Sweden; Department of Geriatric Medicine, Karolinska University Hospital, Huddinge, Sweden. Electronic address: Johan.lokk@karolinska.se.
authors.forename: Johan
authors.initials: J
authors.lastname: Lökk
authors.affiliation: Department of Neurobiology, Care Sciences and Society, Division of Physiotherapy, Karolinska Institutet, Alfred Nobels Alle 23, 141 83 Huddinge, Sweden; Functional Area Occupational Therapy & Physiotherapy, Allied Health Professionals Function, Karolinska University Hospital, Stockholm, Sweden. Electronic address: Erika.franzen@ki.se.
authors.forename: Erika
authors.initials: E
authors.lastname: Franzén
mesh_terms: D000368:Aged; D000978:Antiparkinson Agents / Q000627:therapeutic use*; D001696:Biomechanical Phenomena; D015259:Dopamine Agents / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D009043:Motor Activity / Q000187:drug effects / Q000502:physiology; D010300:Parkinson Disease / Q000188:drug therapy* / Q000503:physiopathology*; D012399:Rotation; D012720:Severity of Illness Index; D016138:Walking / Q000502:physiology
chemical_list: D000978:Antiparkinson Agents; D015259:Dopamine Agents
keywords: Parkinson’s disease; gait; levodopa; turning