Cramps, muscle pain, and fasciculations: not always benign?

Fasciculation and cramps without weakness or muscle atrophy are recognized as a benign syndrome. The authors report a patient with cramp and fasciculation, which persisted for 1 year without abnormal motor unit morphology on EMG before progressive weakness, muscle atrophy, and EMG abnormalities developed. This observation raises the possibility that lower motor neuron hyperexcitability may precede motor neuron death in motor neuron disease.