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What is motor neurone disease (MND)? MND is a neurological disease that affects the neurones (nerves) that provide the stimulus to our muscles through which we move, breathe, eat and drink. The disease is given different names depending upon how the symptoms present themselves. All forms of the disease are ultimately fatal. The three main forms are: amyotrophic lateral sclerosis (ALS), progressive muscular atrophy (PMA) and progressive bulbar palsy (PBP).
In North America ALS is also known as Lou Gehrig's Disease after the famous baseball player whose career was cut short by development of the disease.
Motor neurones are classified as upper and lower motor neurones. Upper motor neurones descend from the brain to the brain stem and the spinal cord; lower motor neurones extend from the brain stem and the spinal cord to the muscles. When the upper motor neurones alone are affected the disease has two names: (i) if limb involvement is predominant the disease is called progressive lateral sclerosis; (ii) if brain stem involvement is predominant the disease is called progressive pseudobulbar palsy. When lower motor neurones alone are affected the disease is called progressive muscular atrophy. When both upper and lower motor neurones are
involved the disease is called amyotrophic lateral
sclerosis. This is the most common form. Motor neurone disease is an adult disease, being uncommon in people aged less than 30. The mortality rate of the disease increases with age, in Australia reaching its peak at around 75 years of age. In 2009 the number of deaths in Australia was 594 - more than one per day. The mortality rate for males is higher than that for females. While it is difficult to estimate very precisely the number of cases in Australia at any one time, it is thought to be about 1,400.
One of the most important things that people can do when newly diagnosed with MND is to contact their local MND Association to take advantage of the information and services provided by them. Australian MND Associations can be contacted through the MND Australia web site. MND Associations in other countries can be contacted through the International Alliance web site Glossary: Amyotrophic - muscle wastingAmyotrophic lateral sclerosis - the form of the disease caused by deficits of upper and lower motor neurones Atrophy - wasting away Bulbar - pertaining to the brain stem or bulb (the region containing the lower motor neurones for the muscles of speech, swallowing and other functions) Lateral - refers to the lateral columns of the spinal chord through which the motor pathways descend from the brain to the motor neurones for the limbs and trunk Lesion - pathological or traumatic discontinuity Palsy - paralysis Progressive - continuing deterioration Progressive bulbar palsy - progressive weakness of (mainly) speech and swallowing owing to lower motor neurone involvement Pseudobulbar palsy - progressive weakness of (mainly) speech and swallowing owing to upper motor neurone involvement Sclerosis - fibrous tissue overgrowth following the loss of nerves and nerve pathways |
Scientific terms
Aetiology – study of the factors that cause disease
ALS – amyotrophic lateral sclerosis, a common form of MND
Androgen – male hormone
Axon – the fibre along which impulses are conveyed from one part of the nervous system to another
Chelate – a chemical compound in which a metal is combined into a molecule with a ring structure. Used in the treatment of metal poisoning.
CNS – central nervous system (brain, spinal column)
Ephs, Ephrins – axon guidance molecules
Innervate – to supply with a nerve
Intrathecal injection – injection of a substance through the theca (sheath) of the spinal cord,
Ligand – a molecule that binds to another molecule
MND – motor neurone disease
Motor cortex – the area of the frontal lobe of the cerebral cortex concerned with primary motor control of the body
mRNA – messenger ribonucleic acid
Multifactorial – arising from the action of many factors
Neuron, neurone – a conducting cell of the nervous system
Neurotrophic – concerned with the nutrition and maintenance of tissue as controlled by the nervous system
Pathoaetiology – joint study of the causes of disease and their structural/functional changes
Pathology – study of the structural/functional changes caused by disease
Peptide – a compound containing one or more amino acids
Polyclonal – pertaining to several clones; derived from different cells
Polygenetic – cumulative genetic factors
Rapsyn – neuromuscular junction protein
Receptor – a sensory nerve-ending that responds to stimuli, or a molecular structure that binds to specific substances
SOD – superoxide dismutase. An enzyme that protects cells against dangerous levels of superoxide.
Synapse – the site at which an impulse is transmitted from one neurone to another either electrically or chemically
Trophic – pertaining to nutrition