What is CP?

Diagnosis of Cerebral Palsy

Cerebral Palsy (CP) simply means that there has been some injury to the brain during development which has resulted in difficulty transmitting the necessary impulses from the brain to the muscles for coordinated movement.

Many children born prematurely will develop some movement difficulties related to early neurological injury.  These impairments emerge slowly over time and are typically not evident during the newborn period.  Most mild motor abnormalities noticeable during the first few months of life will improve and may completely resolve with time.  When motor impairment persists, a diagnosis of cerebral palsy may be considered. 

 About 10% of children born at birth weights of less than 1000 grams will eventually receive a diagnosis of cerebral palsy (McCarton, et. al, 1996; O'Shea, et. al., 1998), a permanent condition.  

Diagnosing cerebral palsy in children born prematurely is often a difficult process which requires observing the child's development over time.

For a diagnosis of CP, the following are necessary: 

1) Movement of muscles has to be adversely affected. 

As voluntary control of the muscles develops with age, it takes time to determine whether and to what extent movement of the muscles has been affected by brain damage (which may or may not have been detected neonatally).  Even with significant PVL or other injury known to be related to cerebral  palsy, cerebral palsy will not be diagnosed unless and until movement is affected.

2)  The motor impairment has to be due to a neurological injury.

That is, the source of the problem is at the level of brain functioning, rather than being due to a problem with another part of the motor system such as the spinal cord or muscle.  Neurological injury may not be apparent using imaging techniques, however, and may be assumed from associated signs and symptoms.

3)  The injury or lesion must be static (not getting worse, but no longer resolving).

A diagnosis of cerebral palsy is not given if the source of the problem is a progressive or deteriorating neurological condition.  Although relatively rare, it is important to rule out such conditions as treatment options may be very different.  Because of the amazing ability of the very young brain to recover from injury, it is also important to wait until the healing process is complete before diagnosing a permanent condition.
The level of impairment may increase with development for children with cerebral palsy.  That is, as a child develops, the impaired use of a muscle or muscle group can become more apparent as he or she is unable to keep up with age expectations. As the demands increase, the impairment becomes more obvious. This is the imapirment which is becoming worse with time; the injury to the brain remains the same.

4) The injury has to occur while the motor system is still developing (usually before, during, or right after birth).

For premature infants, the injuries resulting in CP are thought to most often happen during the perinatal period (right around the time of birth). For some children, however, the injury may have happened prenatally; for others, injury may have happened during the neonatal period.  It can be very difficult to determine exactly when the injury occurred.

5) The impairment in movement does not resolve with time.

Many children with motor problems during infancy do "grow out of" their symptoms, even after the first year of life.  This is not considered to have been cerebral palsy.  (There are a variety of other motor problems associated with prematurity.)  For this reason, medical professionals tend to be very cautious about diagnosing mild to moderate cerebral palsy in prematurely born children during infancy.