Motor neurone disease

Fairly rare condition of unknown cause, although a hereditary influence can be detected in some cases. It involves degeneration of motor nerves, affecting the nerve sheaths running from the cerebral cortex to the spinal cord grey matter and the anterior horn cells in the spinal cord. Early symptoms are muscular weakness, wasting of the muscles in one of the limbs, sometimes in the face or throat. This can end in paralysis. Irritation of the motor nerve cells in the spinal cord grey matter causes small muscular convulsions, together with increasing clumsiness and difficulty in walking, and then general paralysis of almost all muscles. The patient dies of paralysis of the respiratory muscles, or pneumonia caused by choking. There is no effective treatment. Physiotherapy may be beneficial.