CP - cerebral palsy
A heterogeneous disorder of movement and posture that is as a result of a static insult of the brain, there are three distinctive features common to all patients with CP:
- Some degree of motor impairment
- An insult to the developing brain
- A neurological deficit that is nonprogressive, distinguishing it from other motor diseases of childhood
The motor disturbances are often accompanied by disturbances of sensation, perception, cognition, communication, and behavior. Insult to the brain generally occurs between the time of conception and age 2.
While the neurological deficit is permanent and nonprogressive, the effect can be dynamic due to the individuals changes as they grow and develop, which can lead to progressive disability. The prevalence of CP is about 2 per 1000 live births, meaning there are about 400,000 children with CP in the US at any one time. More recently CP numbers have increased due to better neonatal premature care.
80% of cases of CP are due to antenatal cerebrovascular haemorrhage or ischemia, cortical migration disorders or structural maldevelopment of the brain.
Most forms are diagnosed in the first 18 months, as children fall behind on developmental milestones and presenting with hyper or hypotonia. Children will also present with feeding difficulties, asymmetric hand function and abnormal gait. Primitive reflexes may also persist beyond the normal point of disappearance.
Classification can be based on a number of different elements, we have summed up some of the key classifications below:
- Geographic (based on the anatomic region of the body affected)
- Monoplegia (very rare, only one extremity affected)
- Hemiplegia (one side of the body is involved, approx 30%)
- Diplegia (most common, approximately 50% of cases, has motor abnormalities in all four extremities, with lower extremities affected more than upper)
- Quadriplegia (all four extremities are equality involved, most have significant cognitive deficiencies)
- Total body (total body involvement with loss of head and neck control with profound cognitive deficit)
- Physiologic classification
- Corticospinal (pyramidal) type
- Spastic - 80% of all cases, causes spasticity (velocity-dependent increse in muscle tone with passive stress) is caused by an exaggeration of the normal muscle passive stretch. There is a deposition of type I collage in the endomysium of the affected muscle leading to thickening and fibrosis. Patients often have simultaneous contractions of normally antagonistic muscles leading to fatigue, loss of dexterity and coordination, and balance difficulties. Joint contractions, subluxation, and degeneration are common.
- Extrapyramidal