Dyskinetic and dystonic cerebral palsy and birth

Movement disorders due to bilirubin toxicity

Advances in the care of neonatal hyperbilirubinemia have led to a decreased incidence of kernicterus. However, neonatal exposure to high levels of bilirubin continues to cause severe motor symptoms and cerebral palsy (CP). Exposure to moderate levels of unconjugated bilirubin may also cause damage to the developing central nervous system, specifically the basal ganglia and cerebellum. Brain lesions identified using magnetic resonance imaging following extreme hyperbilirubinemia have been linked to dyskinetic CP. Newer imaging techniques, such as diffusion tensor imaging or single-photon emission computed tomography, allow quantification of more subtle white matter injury following presumed exposure to unbound bilirubin, and may explain more subtle movement disorders. New categories of bilirubin-induced neurologic dysfunction, characterized by subtle bilirubin encephalopathy following moderate hyperbilirubinemia, have been implicated in long-term motor function. Further research is needed to identify subtle impairments resulting from moderate-severe neonatal hyperbilirubinemia, to understand the influence of perinatal risk factors on bilirubin toxicity, and to develop neuroprotective treatment strategies to prevent movement disorders due to bilirubin toxicity.

Birth-related syndromes of athetosis and kernicterus

"Athetosis," from the Greek athetos, meaning "without fixed position," is a movement disorder first described by Hammond in 1871. The term described slow, irregular continual movements of the distal extremities. In 1983, Foley defined the athetoid syndrome as "a nonprogressive but evolving disorder due to damage to the basal ganglia of the full-term brain … [with] impairment of postural reflexes, arrhythmical involuntary movements, and dysarthria, [but] sparing … sensation, ocular movements and … intelligence." A decade later, "athetoid syndrome" was replaced by "dyskinetic cerebral palsy." Injury to basal ganglia by various mechanisms, including asphyxia, trauma, perinatal strokes, and kernicterus, is known to cause birth-related athetosis. Kernicterus originally described the neuropathology of bilirubin-induced brain injury, where the deep nuclei of the brain stain yellow. Kernicterus now describes the clinical features of chronic bilirubin encephalopathy, which include an extrapyramidal movement disorder, sensorineural hearing loss, impaired upward gaze, and dental enamel dysplasia. Aggressive treatment of perinatal hyperbilirubinemia has led to a decline in kernicterus so that, today, it is a rare cause of dyskinetic cerebral palsy. In this chapter, we provide a historic overview of athetosis and its formerly common cause, kernicterus. We relate earlier terminology to more recent definitions of impairments in dyskinetic cerebral palsy, including dystonia, chorea, and choreoathetosis.

Outcome after intrapartum asphyxia in term infants

Investigatory techniques, particularly magnetic resonance (MR) imaging and spectroscopy, performed in the early neonatal period on infants suspected of intrapartum asphyxia i.e. abnormal fetal heart recording, poor cord gases, low Apgar scores and the need for resuscitation, or with neonatal encephalopathy or seizures, have allowed a much better understanding of the patterns of brain injury and the biochemical processes that follow these events. It is usually possible to distinguish these patterns from those seen in other, often confounding, diagnoses. This has allowed far more precision about the timing of insults and in the prediction of particularly motor, feeding and visual outcome and to some extent intellectual outcome. Long-term neurological and psychometric follow-up of infants in whom detailed perinatal clinical histories and examination, haematological and biochemical investigation and MR brain scans are obtained will allow even more accurate prediction of outcome in the future. Such studies also help to validate standardized neonatal and infant clinical neurological examinations, making them useful tools to predict outcome.

Oral pharmacotherapy for the movement disorders of cerebral palsy

Movement disorders are a well-recognized feature of some patients with cerebral palsy and often require treatment. However, treatments have been symptomatic and empiric, and there have been few pharmacologic studies. The major movement disorders in cerebral palsy are dystonia and the hyperkinesias choreoathetosis and myoclonus. They may occur in combination, often accompanied by spasticity and sometimes by epilepsy. Some drugs are useful treatments for all of these problems, but others may improve one while worsening another. Pitfalls in management include not diagnosing metabolic/degenerative disorders, which may mimic cerebral palsy, or not recognizing reversible complications of cerebral palsy, which may exacerbate symptoms. This review attempts to summarize empiric drug use and recommendations for therapy, drug studies in extrapyramidal cerebral palsy, and prospects for new drugs or models for the problem. Many new pharmacologic agents are available for study in cerebral palsy. Better methods of detecting basal ganglia injury after perinatal injury in asymptomatic infants may allow early intervention in the biologic process of recovery and adaptation.

Dyskinetic cerebral palsy: a clinical and genetic study

The clinical features and family histories of 20 adults with dyskinetic cerebral palsy from 20 families were studied. The majority of the patients showed progressive neurological deterioration in adult life. In only three did the condition stabilise by 10 years of age and in seven there was deterioration after the age of 30. Two patients developed a secondary cervical spondylotic myelopathy. Four patients had affected relatives and there were similar proportions of affected parents and siblings. The family data suggest genetic heterogeneity with autosomal recessive and dominant variants. The existence of an X-linked form cannot be excluded, and the demonstration of an increased paternal age effect among single cases suggests that some of these may arise because of fresh dominant genetic mutation.

Risk factors for cerebral palsy: a case-control study in Greece

The purpose of this study was to investigate the relation between a series of maternal, antenatal, perinatal, socioeconomic and environmental variables and the occurrence of cerebral palsy (CP) in a setting different from those in which previous analytic epidemiologic studies had been undertaken. The study was of case-control design and included 103 children with cerebral palsy born between 1984 and 1988 and residents of the Greater Athens area at any time during 1991 and 1992. Controls were chosen among the neighbors of the index case or were healthy siblings of children with neurological diseases other than CP seen by the same neurologists as the children with CP; a total of 254 control children were eventually included. Statistical analysis was done by modeling the data through unconditional logistic regression. Statistically significant (p < 0.05) risk factors of potential causal importance were: twin membership (OR = 10.2), gestational age (OR = 0.5 per 4 weeks), birth weight conditional on gestational age (OR = 0.9 per 100 g), congenital malformations (OR = 7.5), unhealthy placenta (OR = 6.6), placenta previa (6 cases, no controls), abnormal amniotic fluid (OR = 3.6), head circumference more than 36 cm (OR = 9.0), general anesthesia during labor (OR = 4.3), forceps delivery (OR = 6.8), and birth trauma (OR = 11.5). Among children with no identifiable prenatal risk factors there was no excess prevalence of one or more perinatal risk factors in CP cases compared to controls, which implies that the latter factors impart their effect through interactions with co-existing prenatal or other risk factors.

Birth-weight ratio and cerebral palsy

The birth-weight ratio, a convenient measure of fetal growth, has been used to assess the importance of antecedent and perinatal factors in a retrospective analysis of 605 cases of congenital cerebral palsy. All had been seen by the author at a special clinic over a period of three decades. The ratio (normally 1) is high in the very premature, falls in the middle of the third trimester, then begins to rise again at term. Abnormalities of pregnancy, or a history of maternal pregnancy-losses, depress the ratio perceptibly. In both singletons and twins, there is no significant relationship between a low ratio and the severity of the clinical condition, and presumably the extent of the brain damage. The findings suggest that growth retardation is an association and not a cause of perinatal vascular-anoxic lesions.

Motor function of infants with athetoid cerebral palsy

The motor function of 35 children with athetoid cerebral palsy was examined retrospectively using videotape recordings made at five to eight months of age. Many infants showed asymmetric tonic neck, Moro and Galant reflexes. Movements shown to be difficult included: keeping a symmetric supine posture, isolated movements of the hips and knees, forward extension of the upper extremity, extension of neck and trunk in the prone position and in ventral suspension, flexion of the neck in the traction response, and weight support by the upper extremities. Asymmetric or excessive opening of the mouth was present in all infants. The grade of difficulty for each posture and movement might reflect subsequent motor disability at three years of age.

The changing panorama of cerebral palsy in Sweden. VI. Prevalence and origin during the birth year period 1983-1986

The prevalence and origin of cerebral palsy in children born between 1983 and 1986 are reported. The crude live-birth prevalence was 2.49 per 1000; 1.56 for term births, 0.93 for preterm births. The increasing trend from 1970 persisted and was statistically significant for both groups. The most pronounced increase during 1983-1986 occurred in term cerebral palsy. The increasing use of neuroimaging techniques made the timing of damaging events more reliable. In term cerebral palsy, the origin was convincingly prenatal in 28% of cases and perinatal in 25%. The particular critical period for the brain damage underlying cerebral palsy was considered to be weeks 26-34 of gestation, i.e. when periventricular structures are extraordinarily vulnerable. In term infants, this occurs during late intrauterine life, while in the majority of preterms it occurs in early neonatal life. In total, two-thirds of cerebral palsy lesions might have been acquired during these decisive months of brain development.

Parental age, genetic mutation, and cerebral palsy

Parental age and birth order were studied in 251 patients with cerebral palsy. No parental age or birth order effects were observed in spastic quadriplegia or diplegia, but a paternal age effect was detected in those with athetoid/dystonic cerebral palsy and congenital hemiplegia. These observations indicate that some cases of athetoid/dystonic or hemiplegic cerebral palsy might arise by fresh dominant genetic mutation.

The offspring of people with cerebral palsy

To test a hypothesis that a placental deficit as a possible cause of CP might be transmitted, 88 people with congenital CP were contacted by questionnaire and letters. They had had 122 children, 93 per cent of whom were reported to be normal. The frequency of miscarriages and toxaemia was normal. 5 per cent of the mothers had had emergency caesarean sections. Three mothers also had minor malformations. The mean gestational age of the children was 38.8 weeks and their mean birthweight was 3295g. The mean birthweight of the mothers born preterm was 984g and that of their babies was 3244g. Two of the 122 children had diplegia, four had malformations, one had trisomy 18 and there was one stillbirth.