Submitted on August 19, 2005
Accepted on January 17, 2006
The relation between muscle fiber conduction velocity and fiber size in neuromuscular disorders
Paul J Blijham1*, Henk J Ter Laak2, Helenius J Schelhaas3, Baziel G Van Engelen3, Dick F Stegeman1, and Machiel J Zwarts4
1 Clinical Neurophysiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
2 Neurology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands; Pathology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
3 Neurology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
4 Clinical Neurophysiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands; Neurology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
* To whom correspondence should be addressed. E-mail: p.blijham{at}neuro.umcn.nl.
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 ninety-six 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 is well expressing the relation: MFCV (m/s) = 0.043*MFD (µm) + 0.83. We conclude that fiber diameter determines MFCV largely, independent of the underlying neuromuscular disorders studied.
