Motor Neuron Diseases

Abstract Motor neuron diseases are a group of rare, heterogenous disorders characterized primarily by skeletal muscle weakness. Diseases are classified as affecting primarily upper motor neurons, lower motor neurons, or both. Upper motor neuron diseases are characterized by muscle weakness, hyperreflexia, and spasticity, while lower motor neuron diseases are characterized by weakness, muscle atrophy, and fasciculations. Disease course is typically progressive. Age of onset, symptom severity, and disease course differ depending on the exact diagnosis and neurons affected. Patients with advanced disease may suffer from respiratory, pharyngeal, and skeletal muscle weakness, which have significant implications for preoperative, intraoperative, and postoperative management.