title: Prehension Kinematics, Grasping Forces, and Independent Finger Control in Mildly Affected Patients with Essential Tremor.
abstract: Although the pathophysiology of essential tremor (ET), one of the most common movement disorders, is not fully understood, evidence increasingly points to cerebellar involvement. To confirm this connection, we assessed the everyday hand and finger movements of patients with ET, as these movements are known to be affected in cerebellar diseases. In 26 mildly affected patients with ET (compared to age- and gender-matched controls), kinematic and finger force parameters were assessed in a precision grip. In a second task, independent finger movements were recorded. The active finger had to press and release against a force-sensitive keypad while the other fingers stayed inactive. Finally, control of grip force to movement-induced, self-generated load changes was studied. Transport and shaping components during prehension were significantly impaired in patients with ET compared to controls. No significant group differences were observed in independent finger movements and grip force adjustments to self-generated load force changes. However, in the latter two tasks, more severely affected ET patients performed worse than less affected. Although observed deficits in hand and finger movement tasks were small, they are consistent with cerebellar dysfunction in ET. Findings need to be confirmed in future studies examining more severely affected ET patients.
authors: Department of Neurology, University of Duisburg-Essen, Essen, Germany. kasja.solbach@uk-essen.de.
authors: Kasja
authors: K
authors: Solbach
authors: Department of Neurology, University of Duisburg-Essen, Essen, Germany.|Department of Pediatrics, St. Vinzenz-Hospital, Dinslaken, Germany.
authors: Mareike
authors: M
authors: Mumm
authors: Department of Neurology, University of Duisburg-Essen, Essen, Germany.|Clinical Psychology and Psychotherapy, University of Hamburg, Hamburg, Germany.
authors: Barbara
authors: B
authors: Brandauer
authors: Department of Neurology, Johns Hopkins University, Baltimore, ML, USA.
authors: Martin
authors: M
authors: Kronenbürger
authors: Department of Sport and Health Sciences, Institute of Movement Science, Technische Universität München, 80992, Munich, Germany.
authors: Joachim
authors: J
authors: Hermsdörfer
authors: Department of Neurology, University of Duisburg-Essen, Essen, Germany.
authors: Dagmar
authors: D
authors: Timmann
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001696:Biomechanical Phenomena; D020329:Essential Tremor / Q000503:physiopathology*; D005260:Female; D005385:Fingers / Q000502:physiology; D018737:Hand Strength / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009048:Motor Skills / Q000502:physiology; D055815:Young Adult
keywords: Cerebellar dysfunction; Cerebellum; Essential tremor; Finger movements; Grasping forces; Prehension