Biomaterial Database

Single motor unit H-reflex in motor neuron disorders. 1992

B Soliven, and R A Maselli

Department of Neurology, University of Chicago, Illinois 60637.

The latency fluctuation of single motor unit potentials (MUPH) in the H-reflex is greater than the latency fluctuation of MUPs in the direct (MUPM) and recurrent (MUPF) responses. This has been attributed to the variability in the impulse generation at the site of nerve stimulation, and to the variation in the synaptic delay at the anterior horn cell. We studied the latency fluctuation of single motor unit H-reflex in patients with motor neuron disorders (MND) in comparison with normal subjects. The mean jitter of the H-reflex was 264.3 +/- 17.8 microseconds (mean +/- SEM) in 30 MUPH recorded from 10 patients with ALS, 302.7 +/- 25.2 microseconds in 16 MUPH from 6 patients with chronic motor neuron diseases, as compared with 137.4 +/- 7.3 microseconds in 34 MUPH recorded from 10 normal subjects. This difference, which persisted even after the correction for the latency variation of MUPM, cannot be explained on the basis of an enhanced reciprocal inhibition. Thus, the increased latency fluctuation of the single motor unit H-reflex in patients with MND may reflect changes in the motoneuron pool excitability that may be secondary to altered intrinsic electrophysiological properties of motoneurons, or to an abnormal temporal and spatial summation of synaptic inputs on motoneurons.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D009046	Motor Neurons	Neurons which activate MUSCLE CELLS.	Neurons, Motor,Alpha Motorneurons,Motoneurons,Motor Neurons, Alpha,Neurons, Alpha Motor,Alpha Motor Neuron,Alpha Motor Neurons,Alpha Motorneuron,Motoneuron,Motor Neuron,Motor Neuron, Alpha,Motorneuron, Alpha,Motorneurons, Alpha,Neuron, Alpha Motor,Neuron, Motor
D009134	Muscular Atrophy, Spinal	A group of disorders marked by progressive degeneration of motor neurons in the spinal cord resulting in weakness and muscular atrophy, usually without evidence of injury to the corticospinal tracts. Diseases in this category include Werdnig-Hoffmann disease and later onset SPINAL MUSCULAR ATROPHIES OF CHILDHOOD, most of which are hereditary. (Adams et al., Principles of Neurology, 6th ed, p1089)	Bulbospinal Neuronopathy,Oculopharyngeal Spinal Muscular Atrophy,Progressive Muscular Atrophy,Scapuloperoneal Form of Spinal Muscular Atrophy,Spinal Muscular Atrophy,Adult Spinal Muscular Atrophy,Adult-Onset Spinal Muscular Atrophy,Amyotrophy, Neurogenic Scapuloperoneal, New England Type,Distal Spinal Muscular Atrophy,Hereditary Motor Neuronopathy,Muscular Atrophy, Adult Spinal,Myelopathic Muscular Atrophy,Myelopathic Muscular Atrophy, Progressive,Progressive Myelopathic Muscular Atrophy,Progressive Proximal Myelopathic Muscular Atrophy,Proximal Myelopathic Muscular Atrophy, Progressive,Scapuloperoneal Spinal Muscular Atrophy,Spinal Amyotrophy,Spinal Muscular Atrophy, Distal,Spinal Muscular Atrophy, Oculopharyngeal,Spinal Muscular Atrophy, Scapuloperoneal,Spinal Muscular Atrophy, Scapuloperoneal Form,Adult Onset Spinal Muscular Atrophy,Amyotrophies, Spinal,Amyotrophy, Spinal,Atrophies, Progressive Muscular,Atrophy, Myelopathic Muscular,Atrophy, Progressive Muscular,Atrophy, Spinal Muscular,Bulbospinal Neuronopathies,Hereditary Motor Neuronopathies,Motor Neuronopathies, Hereditary,Motor Neuronopathy, Hereditary,Muscular Atrophies, Progressive,Muscular Atrophy, Myelopathic,Muscular Atrophy, Progressive,Neuronopathies, Bulbospinal,Neuronopathies, Hereditary Motor,Neuronopathy, Bulbospinal,Neuronopathy, Hereditary Motor,Progressive Muscular Atrophies,Spinal Amyotrophies
D010543	Peroneal Nerve	The lateral of the two terminal branches of the sciatic nerve. The peroneal (or fibular) nerve provides motor and sensory innervation to parts of the leg and foot.	Fibular Nerve,Fibular Nerves,Nerve, Fibular,Nerve, Peroneal,Nerves, Fibular,Nerves, Peroneal,Peroneal Nerves
D011930	Reaction Time	The time from the onset of a stimulus until a response is observed.	Response Latency,Response Speed,Response Time,Latency, Response,Reaction Times,Response Latencies,Response Times,Speed, Response,Speeds, Response
D004568	Electrodiagnosis	Diagnosis of disease states by recording the spontaneous electrical activity of tissues or organs or by the response to stimulation of electrically excitable tissue.	Electrodiagnoses
D005260	Female		Females
D006181	H-Reflex	A monosynaptic reflex elicited by stimulating a nerve, particularly the tibial nerve, with an electric shock.	H Reflex,H-Reflexes,H Reflexes,Reflex, H
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man