motor neuron disease
Also written as: MND — motor neuron disease
A group of progressive degenerative disorders affecting motor neurons in the brain and spinal cord.
Full Definition
Motor neuron disease encompasses a spectrum of progressive neurodegenerative conditions characterized by selective loss of motor neurons in the cerebral cortex, brainstem, and spinal cord. This umbrella term includes amyotrophic lateral sclerosis (ALS), progressive muscular atrophy, progressive bulbar palsy, and primary lateral sclerosis. These conditions present with varying combinations of upper and lower motor neuron signs, leading to progressive weakness, muscle atrophy, and eventual respiratory failure. Diagnosis is primarily clinical, supported by electromyography, and treatment focuses on symptomatic management and supportive care. The heterogeneity of presentation makes accurate classification important for prognosis and research purposes.
Usage
Usage note: Use 'neuron' not 'neurone' in American medical writing; hyphenate when used as compound adjective.
In Context
- "The patient's progressive weakness and fasciculations raised suspicion for motor neuron disease." — Neurology consultation
- "Motor neuron disease encompasses several distinct clinical phenotypes with varying prognoses." — Medical education material