Relation between muscle fiber conduction velocity and fiber size in neuromuscular disorders.
To determine the relation between muscle fiber conduction velocity (MFCV) and muscle fiber diameter (MFD) in pathological conditions, we correlated invasively measured MFCV values with MFD data obtained from muscle needle biopsies in 96 patients with various neuromuscular disorders. MFCV was significantly correlated with MFD and independent of the underlying disorder. Pathological diameter changes were fiber-type dependent, with corresponding MFCVs. A linear equation expresses the relation well: MFCV (m/s)=0.043.MFD (microm)+0.83. We conclude that fiber diameter determines MFCV largely independent of the underlying neuromuscular disorders studied.
Blijham
P J
PJ
Department of Clinical Neurophysiology, Institute of Neurology 920, Radboud University Nijmegen Medical Centre, PO Box 9101, 6500 HB Nijmegen, The Netherlands. p.blijham@neuro.umcn.nl
ter Laak
H J
HJ
Schelhaas
H J
HJ
van Engelen
B G M
BG
Stegeman
D F
DF
Zwarts
M J
MJ
D000328:Adult; D000368:Aged; D001707:Biopsy, Needle; D004576:Electromyography; D019054:Evoked Potentials, Motor / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009046:Motor Neurons / Q000502:physiology; D018485:Muscle Fibers, Skeletal / Q000473:pathology* / Q000502:physiology* / Q000648:ultrastructure; D018482:Muscle, Skeletal / Q000294:innervation / Q000473:pathology / Q000503:physiopathology; D009468:Neuromuscular Diseases / Q000473:pathology* / Q000503:physiopathology*