Motor neurone disease is a rare condition that progressively damages parts of the nervous system. This leads to muscle weakness, often with visible wasting.
Symptoms of motor neurone disease typically follow a pattern that involves three stages: the initial, advanced and end stage. Initial symptoms can be grouped into limb-onset disease, bulbar-onset disease, and respiratory-onset disease depending on the region of the body in which symptoms first appear. These symptoms include muscle weakness and wasting, difficulty with speech and swallowing, and difficulty breathing. Advanced stage symptoms include increased muscle weakness, excess saliva, excessive yawning, emotional changes, mental deficiencies, and breathing difficulties. End stage symptoms usually involve widespread muscle paralysis and increased difficulty breathing.
Motor neurone disease is caused by the degeneration and loss of function of motor neurones in the brain and spinal cord. The exact cause of this loss of function is unclear but a number of internal and external factors impacting the correct functioning of motor neurones have been suggested.
Currently, there is no cure for motor neurones disease. Treatment therefore involves symptom relief and monitoring the progression of the disease.