What is Motor Neurone Disease?
Motor Neurone Disease (MND) is the name given to a group of related diseases affecting the motor neurones in the brain and spinal cord.
The effects of MND vary from one person to another as does the rate of progression. Being well informed and planning ahead can help to make the best use of the present time, and enable people with MND to achieve the best possible quality of life.
Some people may develop weakness and wasting in the muscles supplying the face and throat, causing problems with speech and difficulty chewing and swallowing.
Who gets MND?
MND is not contagious. It can affect any adult at any age but most people who have MND are over the age of 40 and the highest incidence is in the 50-70 age range. Men are affected slightly more often than women.
Precise figures for incidence and prevalence of MND are still uncertain. The incidence (the number of people who will develop MND in any one year) is approximately 2 per 100,000; the prevalence (the number of people who actually have MND at any one time) is thought to be approx 7 per 100,000. The estimated number of people with MND in the UK is up to 5,000.
How is MND Diagnosed?
There is no specific test for MND and it may be difficult to diagnose with certainty in the early stages of the disease because the pattern of symptoms varies between individuals and may be similar to those seen in other conditions. The neurologist (who usually makes the diagnosis) will probably carry out a number of specialised tests in order to eliminate other conditions as well as giving the person with MND a thorough physical examination in order to confirm the diagnosis.
What causes MND?
The cause of MND is not yet known, but a great deal of research work is being carried out, and encouraging advances are being made in understanding both the disease process and the way motor neurones function.
What can be done to help?
Given that MND is a progressive condition, it is important to plan ahead and find out in advance about the services or equipment which may be needed. A range of professionals are employed by Health and Social Services Departments who can help people with MND and their families to live with the condition.
A range of services are available via the Association to ensure that people with MND are enabled to make informed choices about living with the disease.
For more information, click here to visit the Motor Neurone Disease Association national web site.
The types of Motor Neurone Disease
There are two types of motor neurone. Upper motor neurones, which have long, thin nerve trunks connecting the brain to the spine. Within the spine, they connect with the lower motor neurones which, in turn, have nerve trunks connecting to the muscles of the body.
In most cases of MND, degeneration of both the upper and lower motor neurones occurs. This condition is called Amyotrophic Lateral Sclerosis (ALS), characterised by muscle weakness, stiffness and fasciculations (muscle twitching) or, when the muscles involved in speech and swallowing are solely affected, Progressive Bulbar Palsy (PBP).
There are also less common forms in which a more selective degeneration of either the upper motor neurones (such as Primary Lateral Sclerosis, PLS) or lower motor neurones (such as Progressive Muscular Atrophy, PMA) is observed.
There is considerable overlap between these forms of MND. People with PMA in time develop upper motor neurone involvement and in both PMA and ALS some people may eventually experience speech and swallowing difficulties in varying degrees.
It must be stressed that MND affects each individual very differently in respect of initial symptoms and the rate of progression of the illness. In most cases MND is steadily progressive and an average course is two to five years. However, the progression of the disease is variable and a small number of people with MND have lived for ten years or more.
