Neurophysiologic evaluation of lower motor neuron damage in tetraplegia

• Published in: Muscle & nerve Vol. 21; no. 10; pp. 1321 - 1323
• Main Authors: Gorman, Peter H., Kikta, Donald G., Peckham, P. Hunter
• Format: Journal Article
• Language: English
• Published: New York John Wiley & Sons, Inc 01-10-1998; Wiley
• Subjects: Biological and medical sciences; Cell Count; Electromyography; Humans; Magnetic Resonance Imaging; Medical sciences; Motor Neurons - pathology; Motor Neurons - physiology; motor unit counting; Nervous system (semeiology, syndromes); Nervous system as a whole; Neurologic Examination; Neurology; Neurophysiology; Quadriplegia - diagnosis; Quadriplegia - pathology; Quadriplegia - physiopathology; spinal cord injury; tetraplegia; Human; Electrodiagnosis; Tetraplegia; Nervous system diseases; Motor system disorder; Electromyography; Motor neuron; Neurological disorder; Motor unit
• ISSN: 0148-639X; 1097-4598
• DOI: 10.1002/(SICI)1097-4598(199810)21:10<1321::AID-MUS12>3.0.CO;2-4

We quantitatively investigated the extent of damage to motor neurons in tetraplegic subjects. Numbers of motor units in the patients were significantly lower for thenar, wrist extensor, and biceps brachii as compared to controls. Reduction in counts occurred even when M‐response amplitudes were normal. Standard electromyography suggested a surprising frequency of lower motor neuron dysfunction below the level of injury. These results confirm previous reports and add data on motor units in the biceps brachii. © 1998 John Wiley & Sons, Inc. Muscle Nerve 21:1321–1323, 1998.