Description

Cerebral palsy (CP) describes a group of disorders of movement and posture, limiting activity, attributed to nonprogressive underlying brain pathology. The motor disorders of CP are often accompanied by disturbances of sensation, cognition, communication, perception, and/or behavior or by a seizure disorder:

• Spastic (pyramidal; 75%): increased deep tendon reflexes, sustained clonus, hypertonia, and the clasp-knife response:
  • Spastic diplegia: lower extremity involvement
  • Spastic hemiplegia: one side of the body involved
  • Spastic quadriplegia: total body involvement; usually associated with dystonia, dysphagia, and dysarthria
• Dyskinetic (10%): fluctuating tone, rigid total body involvement by definition; persistent primitive reflex patterns (asymmetric tonic neck reflex, labyrinthine)
  • Athetoid: slow writhing movements (or chorea; rapid, random, jerky movements)
  • Dystonic: posturing of the head, trunk, and extremities
• Ataxic (<10%): characterized by cerebellar signs (ataxia, dysmetria, past pointing, tremor, nystagmus) and abnormalities of voluntary movement
• Mixed (10%): two or more types codominant, most often spastic and dyskinetic
• Other (10%): criteria for CP met, but specific subtype cannot be defined
• Extrapyramidal: sometimes applied to nonspastic types of CP as a group

Epidemiology

• ~50% of cases are associated with prematurity.
• Increased concordance among monozygotic versus dizygotic twins in some studies (not in others)
• Intrauterine growth retardation (IUGR) more common in CP than controls, especially for full-term infants in whom CP develops
• Male > female (1.3:1)
• Inconsistent relationship to maternal age, socioeconomic status, and parity
• Prenatal factors are more strongly associated with subsequent CP than are perinatal or postnatal factors; however, individual risk factors are poorly predictive of subsequent CP in the individual child.
• Perinatal asphyxia accounts for only ~9% of CP; diagnosis requires evidence of hypoxic-ischemic insult, severe encephalopathy (e.g., neonatal seizures, severe hypotonia), and consistent laboratory/radiologic findings.
• Increased with multiple gestation (10% were twins in one study)
• Prevalence ~2–3/1,000

Etiology

• Not apparent in most cases. Some studies suggest that the presence of chorioamnionitis; mild or even subclinical infection may have increased association with CP.
• Epidemiologic studies indicate two types of associated vulnerability to CP:
  • Prematurity: Vulnerability of the periventricular white matter between 28 and 32 weeks of gestation results in periventricular leukomalacia.
  • IUGR: fetal growth retardation associated with CNS dysgenesis, non-CNS malformation, teratogens, growth retardation, evidence of hypoxic-ischemic encephalopathy

Commonly Associated Conditions

• Sensory
  • Sensorineural and conductive hearing loss
  • Impaired visual acuity
  • Oculomotor dysfunction
  • Strabismus
  • Cortical visual impairment
  • Somatosensory impairments
• Cognitive/developmental
  • Intellectual disability in ~50%, especially in spastic quadriparesis
  • Autism, ADHD
  • Language and learning disabilities
  • Dysarthria
  • Sleep and behavioral disturbances
• Neurologic
  • Seizures
  • Hydrocephalus
• Musculoskeletal
  • Contractures
  • Hip subluxation/dislocation
  • Scoliosis
  • Osteoporosis
• Cardiorespiratory
  • Upper airway obstruction
  • Aspiration pneumonitis
  • Restrictive lung disease/thoracic deformity
  • Reactive airway disease
• GI/nutritional
  • Poor growth
  • Gastroesophageal reflux
  • Constipation
  • Oral motor dysfunction/dysphagia
• Urinary: neurogenic bladder
• Skin: decubitus ulcers
• Dental
  • Malocclusions
  • Caries
  • Gingival hyperplasia
  • Abnormalities of enamel (congenital)