| Proportion of CP cases | Common causes | Infants affected | Common clinical features |
Infants and young children | Children >5 years old |
Spastic subtypes | | | | | - Increased tone
- Signs of upper motor neuron syndrome
- Brisk deep-tendon reflexes
- Extensor plantar response
- Clonus
- Contractures of affected muscles
|
Spastic diplegia* | 13 to 25% | - Most commonly associated with PVL
| - Preterm infants
- Risk increases with decreasing gestational age
| - First few months – Hypotonia of the lower limbs with delayed functional maturation
- By 6 months – Spasticity involving ankle plantar flexors and hip adductors
- Crawling may be combat style
| - Lower limbs are more affected than the upper limbs
- Affected patients have flexion, adduction, and internal rotation of the hips with frequent contractures of the hip flexors, hamstring, and calf muscles
- Variable degrees of flexion at the elbows and knees
- Reduced limb length and muscle bulk in lower extremities
|
Spastic hemiplegia* | 21 to 40% | - Neonatal stroke
- Prenatal circulatory disturbances
- Brain maldevelopment
| - Term infants of normal birth weight
| - Motor asymmetry (may not be apparent in the newborn period)
- Early (before age 12 months) hand dominance
- Inability to use both hands in midline or to reach out with the affected limb
- Abnormal posturing on one side
- In prone position, the affected upper limb provides decreased support, and movement of the affected leg is diminished
- In a sitting position, the affected leg tends to extend
- Protective reactions that appear at 5 to 8 months of age are asymmetric
- Over first 1 to 2 years, movement and tone on the affected side typically decrease before tone and tendon reflexes abnormally increase
- Typical posture (refer to description to the right) appears by age 2 years in most cases
| - One side of the body is affected
- The arm typically is more affected than the leg
- The arm is adducted at the shoulder and flexed at the elbow, the forearm is pronated, and the wrist and fingers are flexed with the hand closed
- The hip is partially flexed and adducted, and the knee and ankle are flexed; the foot may remain in the equinovarus or calcaneovalgus position
- Most children also have sensory deficits
- In mildly affected patients, postural abnormalities are more apparent during walking or running; however, unless severe intellectual disability is present, independent walking usually occurs at the appropriate age or is only slightly delayed
|
Spastic quadriplegia* | 20 to 43% | - Congenital infection
- Cerebral dysgenesis
- Perinatal or postnatal events
| - Most commonly term SGA infants, but can also occur in preterm infants
| - Moderate or severe psychomotor delay
- Poor head control
- Spasticity may begin by 2 to 3 months of age
- Adduction of the thighs results in typical scissoring of the legs
- By 9 to 10 months of age, infants when pulled to sitting are unable to flex the legs and have poor truncal balance
| - All limbs are affected
- Upper limbs may be equally or more involved than lower limbs
- Children often have severe functional impairment
- Feeding difficulties, chronic respiratory insufficiency, and seizure disorder are common
|
Dyskinetic subtypes | 12 to 14% | - Most cases are caused by severe perinatal asphyxia resulting in injury to the thalamus, basal ganglia, hippocampus, reticular formation, and/or cerebellum
- Severe hyperbilirubinemia (kernicterus) can cause choreoathetotic CP
| - Predominantly term infants
| In early infancy: - Reduced spontaneous movement
- Hypotonia at rest, variable tone with movement or emotion
- Oromotor incoordination
- Persistence of primitive reflexes
- Involuntary grimacing
- Drooling
- Delayed psychomotor development
- Head can be persistently turned
- Involuntary movements are apparent
- Abnormal posturing:
- Extension patterns in the supine position
- Flexion with shoulder retraction in the prone position
- Head usually is persistently turned to one side
| - Involuntary movements
- Contractures are not common but may evolve later in life
- Variable degree of dysarthria and intellectual disability
|
Choreoathetotic CP: - Chorea consists of rapid, irregular, unpredictable contractions of individual muscles or small muscle groups that involve the face, bulbar muscles, proximal extremities, and fingers and toes
- Athetosis consists of slow, smooth, writhing movements that involve distal muscles
- Movements may be induced or accentuated by emotion or change in posture
- Athetosis is most apparent during reaching
- Stress, excitement, or fever may exacerbate chorea
- Primitive reflexes often are retained
- Oropharyngeal difficulties occur commonly
|
Dystonic CP: - Repetitive, patterned, twisting, and sustained movements of the trunk and limbs that may be either slow or rapid
- Pyramidal signs and anarthria may occur
- "Tension," a sudden involuntary increase in tone affecting both flexor and extensor muscles, may occur during attempted movement or with emotion
- Tendon reflexes are normal or may be difficult to elicit
- Clonus and extensor plantar responses are absent
|
Ataxic CP | 4 to 13% | - Most cases are caused by early prenatal events
- Etiology is frequently unknown
- Some cases have genetic causes, including:
- Cerebellar hypoplasia
- Granule cell deficiency
- Joubert syndrome
- Rarely associated with congenital hypoplasia of the cerebellum
| | - Hypotonia¶ and incoordination
- Motor milestones and language skills typically are delayed
| - Ataxic movements
- Widespread disorder of motor function
- Ataxia usually improves with time
- Speech typically is slow, jerky, and explosive
|