Diagnostic investigation and multidisciplinary management in motor neuron disease.

Amyotrophic lateral sclerosis (ALS) is the most common adult-onset motor neuron disease. ALS is a progressive neurodegenerative disorder, involving motor neurons in the cerebral cortex, brainstem and spinal cord, presenting with a combination of upper and lower motor neuron signs. Etiology remains undetermined, although a multifactorial origin is widely accepted including genetic factors, auto-immunity, oxidative stress, glutamate excitotoxicity and abnormal neurofilament aggregation. The absence of specific diagnostic testing, and variable clinical presentations make the diagnosis of ALS challenging, relying upon correlation of clinical, electrophysiological and neuroimaging data. The disease is relentlessly progressive, with dysarthria, dysphagia, tetraparesis, and respiratory insufficiency due to ongoing respiratory muscle paresis. There is no specific treatment for ALS. Riluzole, a glutamate antagonist, is the only FDA approved drug for ALS, but has only a modest effect on survival. The multiplicity and progressiveness of the disabilities in ALS, highlights the need for a coordinated multidisciplinary rehabilitation program managing symptoms, respiratory care, dysphagia and nutrition, dysarthria and communication, physical and occupational therapy. The main goals are to prolong independence, prevent complications and improve quality of life.