A brief overview of conditions related to physical disabilities and possible underlying causes for them... take a look......




Spina Bifida

Down Syndrome

Cerebral Palsy


Cleft Lip/Cleft Palate

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What might cause a physical disability?

Some people are born with physical disabilities. There are two types of internal causes for physical disabilities.

I. Chromosome changes occur if either the male or female sex cell individually divides the wrong way, or the zygote itself divides abnormally after the sperm and egg have joined.

II. Environmental changes are the result of one or both of the child's parents' exposure to something in the environment, such as:


There are also external causes of physical disabilities that are a direct result of things that happen to people after they are born, such as:

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There are MANY kinds of physical disabilities. Focus on a few.....


This disease is caused when a child's spinal cord doesn't develop properly. In this case, the child's backbones don't close around the spinal cord, which leaves part of the spinal cord's covering or the cord itself is exposed. The nerves in this region then can't work correctly, because they do not connect inside the body.

The higher up the back this defect is located, the worse the handicap will be, since more nerves are affected in that area.


Spina bifida can result in other disabilities as well:


Children with spina bifida cannot walk by themselves and must use a wheelchair, leg braces, or crutches in order to get around.

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Down syndrome occurs when either the sperm or egg cell has one extra chromosome, resulting in a fertilized egg with 47 chromosomes instead of the normal 46.

This disability affects more than 7000 children each year!


Some signs that may indicate Down syndrome are:


Other problems associated with this disease include:

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This disorder affects the brain and the muscles, which means it affects how a child learns and grows. It is caused when the parts of the brain that control movement are damaged.


There are several additional disabilities that can affect people with cerebral palsy. Not all sufferers have these problems. They can include:


There are also several different types of cerebral palsy:


This type of CP is characterized by stiff movements of the body.



This type of CP is characterized by involuntary/uncontrolled movements. Movements are jerky at some times and floppy at others.

Special problems can arise in the areas of:



This type of CP is caused by damage to the cerebellum, resulting in off-balance movements and faulty judgement of distance.

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These conditions are characterized by a split in the upper lip or a groove along the ridge of the roof of the mouth. They are always corrected when the child is very young.

There are disabilities that can accompany a cleft lip or cleft palate, such as:

Fortunately, problems like these are almost always overcome!


Check out The Disability Barn for more information on physical disabilities.

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Meyer, Donald J; Vadasy, Patricia F; Fewell, Rebecca R. Living with a Brother or Sister with Special Needs. University of Washington Press, Seattle, 1985.

How much do you know?

1. What are the three types of cerebral palsy? Answer

2. How many children per year does Down syndrome currently affect? Answer

3. What are the internal causes of physical disabilities? Answer

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Last updated 12/2/97

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1. spastic, athetoid, and ataxic Back to question 2























2. more than 7000 Back to question 3























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