Types of CP(A) Classification By Number of Limbs Involved
(1) Quadriplegia - all 4 limbs are involved.
(2) Diplegia - all four limbs are involved. Both legs are more severely affected than the arms.
(3) Hemiplegia - one side of the body is affected. The arm is usually more involved than the leg.
(4) Triplegia - three limbs are involved, usually both arms and a leg.
(5) Monoplegia - only one limb is affected, usually an arm.
(B) Classification By Movement Disorder
(1) Spastic CP- Spastic muscles are tight and stiff, and have increased resistance to being stretched. They become overactive when used and produce clumsy movements. Normal muscles work in pairs: when one group contracts, the other group relaxes to allow free movement in the desired direction. Spastic muscles become active together and block effective movement. This muscular "tug-of-war" is called co-contraction.
Spasticity may be mild and affect only a few movements, or severe and affect the whole body. The amount of spasticity usually changes over time. Therapy, surgery, drugs and adaptive equipment may help to control spasticity. Damage to the brain's cerebral cortex is generally the cause of spastic cerebral palsy.
(2) Athetoid CP- Athetosis leads to difficulty in controlling and co-ordinating movement. People with athetoid cerebral palsy have many involuntary writhing movements and are constantly in motion. They often have speech difficulties. Athetoid cerebral palsy results from damage to the basal ganglia in the midbrain. It was once common as a result of blood type incompatibility, but is now rarely seen.
(3) Ataxic CP- Ataxic CP is the least common form of cerebral palsy. People with ataxic CP have a disturbed sense of balance and depth perception. They usually have poor muscle tone (hypotonic), a staggering walk and unsteady hands. Ataxia results from damage to the cerebellum, the brain's major centre for balance and co-ordination.
(C) Combined Classifications
The classifications of movement disorder and number of limbs involved are usually combined (e.g. spastic diplegia). These technical words can be useful in describing the type and extent of cerebral palsy, but they are only labels. A label does not describe an individual.