Cerebral palsy (CP) is a group of permanent movement disorders caused by damage to or abnormal development of the brain before, during, or shortly after birth. It is the most common motor disability of childhood, affecting roughly 1.5 to 3.5 per 1,000 live births depending on the region, and it looks different in almost every person who has it. Some children walk independently with a slight limp; others use powered wheelchairs and communicate through eye-tracking devices. The brain injury itself does not worsen over time, but its effects on the body can change as a person grows and ages.
What Happens in the Brain
CP results from injury to the developing brain, most often before or around the time of birth. The specific location and extent of the damage determine which type of CP a person develops and how severe it is. In premature infants, the most common form of brain injury is damage to the white matter surrounding the brain’s fluid-filled ventricles. This type of injury, called periventricular leukomalacia, is the leading known cause of CP and cognitive difficulties in babies born early.1PubMed Central. Progress in periventricular leukomalacia The white matter in this region carries signals from the brain to the muscles, so when it is damaged, motor control suffers. Inflammation plays a key role in the process, and the immature brain is particularly vulnerable because its blood supply and cellular defenses are still developing.2PubMed. Periventricular leukomalacia, inflammation and white matter lesions within the developing nervous system
In full-term infants, the injury pattern tends to be different. Damage more often involves the deep gray matter structures (the basal ganglia and thalamus) or the cerebral cortex itself, and it is frequently linked to oxygen deprivation around the time of delivery. Brain imaging studies comparing subtypes of CP have found that children with the involuntary-movement (athetoid) form tend to have more severe deep brain abnormalities, while those with the stiff-muscle (spastic) form show changes concentrated around the ventricles and nearby white matter.3PubMed Central. Anatomical characterization of athetotic and spastic cerebral palsy using an atlas-based analysis
Causes and Risk Factors
There is rarely a single, tidy explanation for why a particular child develops CP. In most cases, multiple risk factors overlap. The largest share of cases originates before or during birth.
Prematurity is the single strongest risk factor. Babies born before 32 weeks of gestation face a dramatically higher chance of CP than those born at term, largely because of the vulnerability of their developing white matter. Hypoxic-ischemic encephalopathy, a condition in which the brain is deprived of oxygen and blood flow around the time of delivery, is another major cause and remains one of the leading contributors to CP and newborn death in lower-income countries.4Journal of Pharmacy & Pharmacognosy Research. Effect of erythropoietin on cerebral palsy prevention in hypoxic-ischemic encephalopathy
Maternal infections during pregnancy also raise the risk. A large study found that chorioamnionitis (infection of the membranes surrounding the fetus) roughly tripled the odds of CP, while other genitourinary infections and respiratory infections during pregnancy each carried a smaller but still meaningful increase in risk.5PubMed Central. Maternal Infections During Pregnancy and Cerebral Palsy in the Child The connection between infection and brain injury appears to run through inflammation: the fetus’s own inflammatory response can damage developing nerve tissue, even when the infection itself does not cross the placenta.6PubMed. Chorioamnionitis and cerebral palsy: lessons from a patient registry Researchers have been working to pin down the exact severity and duration of inflammatory exposure required to cause lasting damage, and that question remains open.7PubMed. Proinflammatory cytokines: a link between chorioamnionitis and fetal brain injury
A smaller but important share of CP occurs after the newborn period. Infections like meningitis, traumatic brain injury, stroke in infancy, and severe jaundice can all cause the kind of brain damage that leads to CP. In some low-income settings, postneonatal causes such as malaria and malnutrition account for a much larger proportion of cases than they do in wealthier countries.8PubMed Central. Global prevalence of cerebral palsy: A systematic analysis
The Growing Role of Genetics
For decades, CP was viewed almost entirely as the result of environmental insults: oxygen deprivation, infection, bleeding in the brain. Genetics was thought to explain only a tiny fraction of cases, mostly in families with more than one affected child. That picture has shifted considerably. Modern gene-sequencing studies have identified at least 18 genes and 5 types of chromosomal copy-number changes with strong evidence linking them to CP.9PubMed Central. Insights From Genetic Studies of Cerebral Palsy
When researchers sequenced the protein-coding portions of DNA in children with CP who had no family history of the condition, roughly 14 percent turned out to carry likely disease-causing mutations in single genes, and up to about 31 percent had clinically relevant copy-number variations in their chromosomes.10PubMed. Cerebral palsy: causes, pathways, and the role of genetic variants Many of these genes affect early brain development or make the brain more susceptible to the kinds of environmental insults (like oxygen deprivation) that are already known risk factors. In other words, genetics and environment often work together rather than operating as separate causes. The practical upshot is that genetic testing is increasingly becoming part of the diagnostic workup for CP, especially when imaging does not fully explain a child’s condition.11PubMed Central. Genetics of Cerebral Palsy: Diagnosis, Differential Diagnosis, and Beyond
Types of Cerebral Palsy
CP is classified by the type of movement problem and by which parts of the body are affected. The vast majority of cases fall into the spastic type, characterized by stiff, tight muscles. An Australian population study found that about 86 percent of young people with CP had the spastic form.12PubMed Central. Cerebral palsy in Victoria: motor types, topography and gross motor function Within spastic CP, the condition is further described by topography:
- Hemiplegia: one side of the body is affected, usually with the arm more involved than the leg. This accounted for about 35 percent of cases in the same study.
- Diplegia: both legs are primarily affected, with the arms less so. About 28 percent of cases.
- Quadriplegia: all four limbs are significantly affected, often along with the trunk, face, and mouth muscles. About 37 percent of cases, and generally the most severe form.
Beyond spastic CP, two other main types exist. Dyskinetic CP involves involuntary movements that can be slow and writhing (athetoid) or sudden and jerky (dystonic). Ataxic CP, the rarest form, affects balance and coordination, making movements shaky and imprecise. Some people have features of more than one type, described as mixed CP. The labels matter because they guide treatment: therapies that work well for spasticity, for instance, are not necessarily useful for dystonia.
How Cerebral Palsy Is Diagnosed
Historically, many children were not diagnosed with CP until age two or later, because clinicians wanted to wait and see how motor development unfolded. That wait-and-see approach has been falling out of favor. Research now shows that a combination of three tools used in infancy can identify CP with very high accuracy: a standardized neurological exam, observation of an infant’s spontaneous movement patterns (called general movement assessment), and brain imaging such as MRI. Used together in high-risk infants, these three assessments achieved close to 98 percent sensitivity and 99 percent specificity in one pooled analysis.13PubMed Central. The Pooled Diagnostic Accuracy of Neuroimaging, General Movements, and Neurological Examination for Diagnosing Cerebral Palsy Early in High-Risk Infants: A Case Control Study
The general movement assessment, developed by the Austrian neurologist Heinz Prechtl, is particularly useful because it can be done from a simple video recording of a baby moving naturally. When clinicians are trained in the method, their ability to correctly identify abnormal movement patterns and predict CP improves substantially, and this holds true regardless of whether the person reading the video has a medical background.14PubMed Central. Unveiling the Immediate Impact of Prechtl’s General Movement Assessment Training on Inter-Rater Reliability and Cerebral Palsy Prediction Early diagnosis matters because the infant brain is at its most adaptable in the first months of life, and starting therapy early can take advantage of that window.
Once CP is identified, a functional classification system called the Gross Motor Function Classification System (GMFCS) is used to describe a child’s movement abilities on a five-level scale, from Level I (walks without limitations) to Level V (transported in a manual wheelchair). This system has shown high reliability across raters and strong predictive value: the level assigned at age one to two correctly predicted whether a child would walk by age 12 in about three-quarters of positive cases, and correctly predicted non-walking in 90 percent of negative cases.15Developmental Medicine & Child Neurology. The Gross Motor Function Classification System for Cerebral Palsy: a study of reliability and stability over time
Common Accompanying Conditions
CP seldom affects movement alone. The brain damage that disrupts motor pathways often touches areas involved in thinking, sensation, and other functions. About 45 percent of people with CP in one large population study had intellectual disability, and this was strongly linked to more severe motor involvement: intellectual disability was present in nearly half of those who could not walk, compared with about 8 percent of those who could.16PubMed. Intellectual disability in cerebral palsy: a population-based retrospective study The same study found that intellectual disability was associated with epilepsy, more hospital admissions, and lower long-term survival.
Epilepsy itself is common, and its likelihood increases with greater motor and cognitive involvement. Vision problems, hearing loss, speech and language difficulties, and challenges with swallowing and feeding round out the picture. Pain is another major concern, both from the musculoskeletal strain of living with abnormal muscle tone and from the procedures used to manage it. Children with more severe manual and intellectual impairments, as well as those with vision problems, are at particular risk for difficult-to-treat epilepsy.17PubMed. Clinical features associated with epilepsy occurrence, resolution, and drug resistance in children with cerebral palsy
Managing Spasticity With Medication
Because spasticity is the defining feature of most CP, a large share of medical treatment focuses on reducing it. The two most widely used targeted approaches are botulinum toxin injections and baclofen.
Botulinum toxin (commonly known by brand names like Botox) is injected directly into overactive muscles. It works by blocking the chemical signal that tells a muscle to contract, producing a temporary relaxation that typically lasts three to six months. Some biomechanical studies suggest the effects on the muscle itself can persist even longer than the clinical relaxation. A concern raised by researchers is that the muscle wasting caused by the injections may outlast the beneficial relaxation, which is something clinicians weigh when deciding on repeat treatments.18PubMed Central. Botulinum Toxin in the Management of Children with Cerebral Palsy
For children with more widespread and severe spasticity that does not respond well enough to oral medications, intrathecal baclofen is an option. A pump surgically placed under the skin delivers baclofen directly into the spinal fluid, bypassing the bloodstream and reducing side effects like drowsiness. Combining intrathecal baclofen with botulinum toxin injections in targeted muscles can address both the generalized and the focal components of spasticity at the same time.19PubMed. Intrathecal Baclofen Infusion-Botulinum Toxin Combined Treatment Efficacy in the Management of Spasticity due to Cerebral Palsy
Surgical Approaches
When spasticity in the legs is the primary problem and it is not adequately managed by medication and therapy, a neurosurgical procedure called selective dorsal rhizotomy (SDR) may be considered. In SDR, a surgeon identifies and cuts a portion of the sensory nerve rootlets entering the spinal cord that are contributing to excessive muscle stiffness. The goal is a permanent reduction in spasticity, unlike the temporary effect of botulinum toxin. A randomized trial found that children who received SDR followed by physical and occupational therapy showed significantly greater motor improvement at one year than children who received therapy alone, with measurable reductions in muscle stiffness at the knee and ankle and more normal foot contact during walking.20PubMed. Evaluation of selective dorsal rhizotomy for the reduction of spasticity in cerebral palsy: a randomized controlled trial Patient selection is key: SDR works best when spasticity rather than dystonia is the dominant problem and when the legs are the most affected limbs.21PubMed. Selective dorsal rhizotomy for spastic cerebral palsy: a review
Orthopedic surgery addresses the downstream consequences of years of abnormal muscle pull on growing bones and joints. One of the most important targets is the hip. Children with CP, especially those who do not walk, are at high risk for progressive hip displacement because spastic muscles pull the thighbone out of the hip socket over time. Current practice emphasizes regular hip surveillance with X-rays so that problems are caught early. When subluxation is detected, soft-tissue releases around the hip may be performed first. If displacement progresses beyond a certain point, reconstructive bone surgery involving reshaping of the thighbone and/or the hip socket is recommended.22SICOT-J. Hip displacement in children with cerebral palsy: surveillance to surgery – a current concepts review More broadly, orthopedic surgery in CP has shifted toward performing multiple corrections in a single operation (called single-event multilevel surgery) rather than spacing them out over years, which reduces the total number of hospital stays and rehabilitation cycles a child goes through.23PubMed Central. Orthopedic surgery in cerebral palsy: Instructional course lecture
Rehabilitation and Assistive Technology
Physical and occupational therapy are the backbone of CP management at every age. One technique with especially strong evidence for children with hemiplegic CP (where one side is affected) is constraint-induced movement therapy, or CIMT. The idea is to restrain the stronger hand so the child is encouraged to use the weaker one. Animal research has shown that CIMT triggers changes at the protein level in the motor cortex and spinal cord, promoting the formation of new synaptic connections and nerve fibers on the injured side.24PubMed. Proteomic changes of the bilateral M1 and spinal cord in hemiplegic cerebral palsy mouse: Effects of constraint-induced movement therapy In clinical practice, CIMT has been shown to improve hand function in children, and it is one of the most-studied rehabilitation interventions in pediatric CP.
Assistive technology has expanded enormously. For children with very limited hand and arm control, eye-tracking systems can now be used to steer a powered wheelchair, giving them independent mobility they would not otherwise have.25AHFE International. Assistive Technology: Design and Implementation of an Eye Tracking Based Electric Wheelchair Control System for Children with Cerebral Palsy Communication devices using eye gaze, head switches, or touchscreens help people with CP who cannot speak express themselves. Orthotics (braces and splints) are used at virtually every level of severity to support posture and protect joints. The range of available tools continues to grow, and matching the right technology to the right child at the right time is as much an art as a science.
Prevention
Because CP has so many different causes, prevention efforts take several forms. Two strategies have particularly strong evidence behind them. Giving magnesium sulfate to mothers at risk of delivering before 34 weeks of pregnancy reduces the baby’s risk of CP by about 30 percent compared with placebo, and cuts the risk of moderate-to-severe CP even further.26PubMed Central. Antenatal magnesium sulfate for the prevention of cerebral palsy in preterm infants <34 weeks’ gestation: a systematic review and meta-analysis For full-term and late preterm babies who experience oxygen deprivation at birth, therapeutic hypothermia (carefully cooling the baby’s body for about 72 hours) reduces the severity of brain damage from hypoxic-ischemic encephalopathy.27PubMed. Proven Neonatal Neuroprotection Strategies: Magnesium Sulfate and Therapeutic Hypothermia Both interventions are now standard of care in high-resource hospitals.28PubMed Central. Review on Prevention of Cerebral Palsy from the Perspective of Social Pediatrics
Beyond these two headline interventions, basic improvements in prenatal care, obstetric monitoring, neonatal intensive care, vaccination, car-seat use, and treatment of newborn jaundice all contribute to reducing CP rates. In wealthier countries, the overall prevalence of CP has been slowly declining. In lower-resource settings, the picture is different.
Global Disparities
CP prevalence varies widely around the world. High-income countries generally report rates of about 1.5 per 1,000 live births, while some low- and middle-income regions report rates more than double that. A systematic analysis found birth prevalence estimates of roughly 3 to 3.4 per 1,000 in parts of Bangladesh and Moldova.8PubMed Central. Global prevalence of cerebral palsy: A systematic analysis And those figures are almost certainly underestimates, because children with CP in resource-poor settings are more likely to die before being diagnosed and milder cases go unrecognized.
Data from a multinational CP registry of children in low- and middle-income countries illustrate the gap in another way: the median age at diagnosis was three years, roughly 47 percent of children had never received any rehabilitation services, and more than 75 percent of school-age children had no access to education.29PubMed. Epidemiology of cerebral palsy in low- and middle-income countries: preliminary findings from an international multi-centre cerebral palsy register Postneonatal causes like malaria and severe malnutrition also play a larger role in these regions, accounting for more than a third of CP cases in parts of Nigeria compared with roughly 6 percent in Australia. These differences point to prevention opportunities that are highly region-specific.
Aging With Cerebral Palsy
CP is usually discussed as a childhood condition, but the large majority of people who have it live well into adulthood. And aging with CP brings its own set of challenges that the healthcare system has been slow to address. Adults with CP tend to develop chronic health conditions at higher rates and earlier ages than the general population, including fatigue, pain, declining strength, reduced physical activity, and worsening musculoskeletal problems.30PubMed Central. Emerging Issues in Cerebral Palsy Associated With Aging: A Physiatrist Perspective Many adults report that walking becomes harder over time, that swallowing difficulties emerge or worsen, and that energy levels drop. These changes are not caused by new brain damage but by the cumulative strain of decades of compensating for abnormal movement patterns.
A persistent problem is that healthcare providers who treat adults often have little training or experience with CP, since it has traditionally lived in the world of pediatrics. Adults with CP frequently report that their age-related changes and secondary conditions are not recognized or managed by their doctors.31PubMed. Health, mortality, and wellness issues in adults with cerebral palsy The transition from pediatric to adult healthcare remains one of the most difficult passages for people with CP, and the gap in specialized adult services is an area where advocates and researchers are pushing for change.