Cerebral Palsy Overview

Cerebral Palsy

• Cerebral palsy (CP) is a neurodevelopmental disorder beginning in early childhood and lasting throughout life.
• It is a non-progressive central nervous system (CNS) deficit.
• The condition may involve one or several brain areas.
• It results in definite motor and potential sensory abnormalities.
• CP results from in-utero factors, events during labor and delivery, or a range of factors in early childhood development. This includes congenital CP (factors affecting the fetus during womb development) and acquired CP (factors affecting the fetus in earlier childhood development).
• 70-80% of CP cases are attributed to antenatal causes.

Definition

• Cerebral paresis was an original description from Little in 1861.
• Bax (1964) defined CP as a movement and posture disorder resulting from a lesion of the immature brain.
• Mutch and colleagues (1992) introduced a more comprehensive definition of CP. They described it as a group of motor impairment syndromes resulting from brain lesions or anomalies, largely present during the initial stages of development.
• CP describes a group of permanent disorders of movement and posture.
• Activity limitation frequently accompanies CP and are attributed to non-progressive disturbances occurring in the developing fetal or infant brain.
• Sensory, perception, cognition, communication, and behavior disturbances often accompany the motor problems.
• Epilepsy and musculoskeletal issues are secondary complications frequently associated with CP.

Exclusion

• Conditions excluded from the diagnosis of CP are:
  • Disorders of movement/posture with short duration.
  • Disorders of movement/posture due to progressive diseases.
  • Disorders of movement/posture solely due to mental deficiency.

Incidence and Prevalence

• 550,000- 764,000 Americans have a diagnosis of CP.
• 9,750 new cases are reported annually (UCP, 2003).
• The incidence of CP in developed countries is estimated at 2 to 2.5 cases per 1,000 live births.
• Prevalence of CP has increased in industrialized regions.
• Spastic diplegia is more prevalent than other types.
• The incidence is slightly higher in premature infants and those who are underweight for their gestational age.
• CP is slightly more common in males compared to females.

Risk Factors

• Antenatal risk factors include prematurity, low birth weight, intrauterine infections, multiple gestations, and pregnancy complications.
• Perinatal risk factors include birth asphyxia and complicated labor and delivery (approximately 10% of CP cases).
• Postnatal risk factors include accidental harm/injury, head trauma, meningitis/encephalitis, and cardio-pulmonary arrest.
• Obstetrical care, such as magnesium sulfate, antibiotics, and corticosteroids, can reduce CP risk.

Genetic Causes

• Genetics account for approximately 2% of CP cases.
• Examples of genetic conditions linked to CP include familial spastic paraplegia, generalized athetosis, ataxia, Joubert syndrome, Marinesco-Sjogren syndrome, Gillespie syndrome, and Behr syndrome.

Maternal Disorders

• Maternal disorders affecting fetal supply can lead to CP, including bleeding during pregnancy, placental infarction, pre-eclampsia/toxemia, pre-eclampsia, small size for gestational age, diabetes in the mother, and multiple pregnancies.

Infectious Causes

• Meningitis and encephalitis are common infectious causes of CP.
• Other medical conditions include late-onset hydrocephalus and neoplastic intracranial lesions (tumors).

Types of Cerebral Palsy

• CP is categorized into five types: spastic, dyskinetic (athetoid), ataxic, hypotonic, and mixed.
• These classifications relate to the characteristics of muscle tone and movement.
• Muscle tone refers to the stiffness or tension of muscles during movement.

Spastic Cerebral Palsy

• Characterized by stiff muscles in the affected extremities and trunk.
• Movement is slow, and speed attempts result in increased stiffness, though direction tends to be accurate.
• Range of motion is reduced, with contractures and/or deformities developing over time.

Dyskinetic Cerebral Palsy

• Characterized by involuntary movements and variable muscle tone.
• Movement is often described as slow and writhing.
• Reversal and imprecise directions are common.
• Resistance to movement may be seen, especially in rigidity with increased tone in agonist and antagonist muscles.

Hypotonic Cerebral Palsy

• Characterized by decreased resting muscle tension.
• Individuals with hypotonia have decreased ability to generate muscular force.
• Excessively flexible joints.
• Often a transitional stage that can eventually progress to spasticity or athetosis.

Ataxic Cerebral Palsy

• Characterized by poor balance, coordination, and difficulty controlling movement timing and sequence.
• Depth perception and straight-line walking are also challenging.

Acquired Cerebral Palsy

• CP acquired later in childhood, before motor brain maturity, is due to brain damage after birth.
• Infections or head injuries within the first two years of childhood commonly result in acquired CP.

Classification Based on Distribution

• Classification is based on the affected body part(s).
• Terms like monoplegia, diplegia, hemiplegia, and quadriplegia denote the number of limbs involved.

Abnormal Oral Movement Patterns and Posture

• Specific oral features associated with CP include lip retraction (tight lips in a smile posture), jaw thrust/lack of jaw grading (forceful jaw extension), tonic bite (strong and sustained biting), and tongue retraction (tongue held back in mouth, limited mobility). Nasal regurgitation may also occur.