Extraordinary breakthroughs in the molecular pathogenesis of muscle and ner
ve disease have resulted in an evolving genetic classification of neuromusc
ular disorders and the development of new diagnostic methods. This remarkab
le progress has introduced new genetic tests and has changed the indication
s for use of certain invasive diagnostic procedures in the evaluation of ch
ildren with presumed disorders of the motor unit. In this review, we presen
t the current diagnostic approach to the more common neuromuscular diseases
of infancy and childhood and define the diagnostic role of muscle biopsy a
nd pediatric electromyography/nerve conduction studies in the era of geneti
c analysis. (C) 2000 by Elsevier Science Inc. All rights reserved.