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Cerebral palsy refers to nonprogressive syndromes characterized by impaired voluntary movement or posture and resulting from prenatal developmental malformations or perinatal or postnatal CNS damage. Syndromes manifest before age 5 yr. Diagnosis is clinical. Treatment may include physical and occupational therapy, braces, drug therapy or botulinum toxin injections, orthopedic surgery, intrathecal baclofen, or, in certain cases, dorsal rhizotomy.

Cerebral palsy (CP) is a group of syndromes that causes nonprogressive spasticity, ataxia, or involuntary movements; it is not a specific disorder or single syndrome. CP syndromes occur in 0.1 to 0.2% of children and affect up to 15% of premature infants.

Etiology

Etiology is multifactorial, and a specific cause is often hard to establish. Prematurity, in utero disorders, neonatal encephalopathy, and kernicterus often contribute. Perinatal factors (eg, perinatal asphyxia, stroke, CNS infections) probably cause 15 to 20% of cases. Spastic diplegia after premature birth, spastic quadriparesis after perinatal asphyxia, and athetoid and dystonic forms after perinatal asphyxia or kernicterus are examples of types of CP. CNS trauma or a severe systemic disorder (eg, stroke, meningitis, sepsis, dehydration) during early childhood may also cause a CP syndrome.

Symptoms and Signs

Before a specific syndrome develops, symptoms include lagging motor development and often persistent infantile reflex patterns, hyperreflexia, and altered muscle tone.

Categories: Syndromes are categorized mainly as one of the following, depending on which parts of the CNS are malformed or damaged:

• Spastic syndromes occur in > 70% of cases. Spasticity is a state of resistance to passive range of motion; resistance increases with increasing speed of that motion. It is due to upper motor neuron involvement and may mildly or severely affect motor function. These syndromes may cause hemiplegia, quadriplegia, diplegia, or paraplegia. Usually, deep tendon reflexes in affected limbs are increased, muscles are hypertonic, and voluntary movements are weak and poorly coordinated. Joint contractures develop, and joints may become misaligned. A scissors gait and toe walking are typical. In mild cases, impairment may occur only during certain activities (eg, running). Corticobulbar impairment of oral, lingual, and palatal movement, with consequent dysarthria or dysphagia, commonly occurs with quadriplegia.
• Athetoid or dyskinetic syndromes occur in about 20% of cases and result from basal ganglia involvement. The syndromes are defined by slow, writhing, involuntary movements of the proximal extremities and trunk (athetoid movements), often activated by attempts at voluntary movement or by excitement. Abrupt, jerky, distal (choreic) movements may also occur. Movements increase with emotional tension and disappear during sleep. Dysarthria occurs and is often severe.
• Ataxic syndromes occur in < 5% of cases and result from involvement of the cerebellum or its pathways. Weakness, incoordination, and intention tremor cause unsteadiness, a wide-based gait, and difficulty with rapid or fine movements.
• Mixed syndromes are common—most often, with spasticity and athetosis.

Associated findings: About 25% of patients, most often those with spasticity, have other manifestations. Strabismus and other visual defects may occur. Children with athetosis due to kernicterus commonly have nerve deafness and upward gaze paralysis. Many children with spastic hemiplegia or paraplegia have normal intelligence; children with spastic quadriplegia and mixed syndromes may have severe intellectual disability.

Diagnosis

• Cranial MRI

If CP is suspected, cranial MRI is done; it can detect abnormalities in most cases.

CP can rarely be confirmed during early infancy, and the specific syndrome often cannot be characterized until age 2 yr. High-risk children (eg, those with evidence of asphyxia, stroke, periventricular abnormalities seen on cranial ultrasonography in premature infants, jaundice, meningitis, neonatal seizures, hypertonia, hypotonia, or reflex suppression) should be followed closely.

CP should be differentiated from progressive hereditary neurologic disorders and disorders requiring surgical or other specific neurologic treatments. Ataxic forms are particularly hard to distinguish, and in many children with ataxia, a progressive cerebellar degenerative disorder is ultimately identified as the cause. Athetosis, self-mutilation, and hyperuricemia in boys indicate Lesch-Nyhan syndrome (see Inherited Disorders of Metabolism: Lesch-Nyhan syndrome). Cutaneous or ocular abnormalities may indicate tuberous sclerosis, neurofibromatosis, ataxia-telangiectasia, von Hippel-Lindau disease, or Sturge-Weber syndrome. Infantile spinal muscular atrophy and muscular dystrophies associated with hypotonia and hyporeflexia usually lack signs of cerebral disease. Adrenoleukodystrophy begins later in childhood, but other leukodystrophies begin earlier and may be mistaken for CP at first.

Laboratory tests can exclude certain progressive storage disorders that involve the motor system (eg, Tay-Sachs disease, metachromatic leukodystrophy, mucopolysaccharidoses). Other progressive disorders (eg, infantile neuroaxonal dystrophy) may be suggested by nerve conduction studies and electromyography but must be diagnosed clinically or pathologically. Children with pronounced intellectual disability and symmetric motor abnormalities should be evaluated for amino acid and other metabolic abnormalities (see Inherited Disorders of Metabolism).

Prognosis

Most children survive to adulthood. Severe limitations in sucking and swallowing, which may require feeding by gastrostomy tube, decrease likelihood of survival. The goal is for children to develop maximal independence within the limits of their motor and associated deficits; with appropriate management, many children, especially those with spastic paraplegia or hemiplegia, can lead near-normal lives.

Treatment

• Physical and occupational therapy
• Braces, drugs, or surgery to treat spasticity
• Assistive devices

Physical therapy and occupational therapy for stretching, strengthening, and facilitating good movement patterns are usually used first. Bracing, drug therapy, and surgery are used to treat spasticity. Botulinum toxin may be injected into muscles to decrease their uneven pull at joints and to prevent fixed contractures. Drugs such as baclofen Some Trade Names
LIORESAL
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, benzodiazepines (eg, diazepam Some Trade Names
VALIUM
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), tizanidine Some Trade Names
ZANAFLEX
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, and sometimes dantrolene Some Trade Names
DANTRIUM
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may diminish spasticity. Intrathecal baclofen Some Trade Names
LIORESAL
Click for Drug Monograph
(via subcutaneous pump and catheter) is the most effective treatment for severe spasticity. Orthopedic surgery (eg, muscle-tendon release) may help reduce restricted joint motion or misalignment. Selective dorsal rhizotomy may help a few children if spasticity affects primarily the legs and if cognitive abilities are good.

When intellectual and physical limitations are not severe, children should attend mainstream schools. However, some children require varying degrees of lifelong supervision and assistance. Speech training or other forms of facilitated communication may be required. Even severely affected children can benefit from training in activities of daily living (eg, washing, dressing, feeding), which increases their independence and self-esteem and greatly reduces the burden for family members or other caregivers. Assistive devices may increase mobility and communication, help maintain range of motion, and help children and their caregivers with activities of daily living.

Parents of a child with chronic limitations need assistance and guidance in understanding the child's status and potential and in dealing with their own feelings of guilt, anger, denial, and sadness (see Caring for Sick Children and Their Families: Effects on the family). Such children reach their maximal potential only with stable, sensible parental care and the assistance of public and private agencies (eg, community health agencies, vocational rehabilitation organizations, lay health organizations such as the United Cerebral Palsy Association).

Last full review/revision May 2009 by Margaret C. McBride, MD

Content last modified May 2009