title: Reconsideration of the concept of enhanced static fusimotor drive in rigidity in patients with Parkinson's disease.
abstract: The electromyographic responses elicited in the first dorsal interosseus muscle by small muscle stretches or by electrical stimulation of the median nerve were investigated in parkinsonian patients and in age-matched healthy subjects. Stimuli were applied during a steady level of contraction in the intrinsic hand muscle. This ensured comparable levels of excitability in the alpha-motoneurone pool in patients and normals. It was found that the normal short-latency stretch reflex was almost absent in rigid patients, while responses to electrical stimulation of low-threshold nerve fibres were of equal size in both groups. This result suggests that there is a change in fusimotor control of muscle spindles in Parkinson's rigidity without alteration of the central gain of the Ia-transmitted stretch reflex.
authors.affiliation: Neurological Clinic with Clinical Neurophysiology, Alfried Krupp Hospital, Essen, F.R.G.
authors.forename: J
authors.initials: J
authors.lastname: Noth
authors.forename: M
authors.initials: M
authors.lastname: Schürmann
authors.forename: K
authors.initials: K
authors.lastname: Podoll
authors.forename: M
authors.initials: M
authors.lastname: Schwarz
mesh_terms: D004558:Electric Stimulation; D004576:Electromyography; D006801:Humans; D008475:Median Nerve / Q000503:physiopathology; D009119:Muscle Contraction; D009127:Muscle Rigidity / Q000503:physiopathology*; D009132:Muscles / Q000503:physiopathology; D010300:Parkinson Disease / Q000503:physiopathology*; D011930:Reaction Time