20.2.4.1 Introduction

Amyotrophic lateral sclerosis occurs in 5 out of 100,000 people, and occurs more common in men than women. About 10% of cases are familial (genetically linked), and 90% of cases are sporadic (unknown cause). Motor neurone disease usually presents between the ages 50-70 years.

Amyotrophic lateral sclerosis or motor neurone disease is a disorder of the motor neurones of the ventral horn of the spinal cord and the cortical neurones that provide the afferent input to that area. There is a selective loss of the spinal and brainstem motor neurones.

The symptoms of motor neuron disease are muscle wasting, muscle fasciculation, spasticity or stiffness in arms and legs, and overactive tendon reflexes. Motor neurone disease is progressive and fatal. Death usually occurs after 2-3 years with respiratory compromise and pneumonia the most common reasons for death.