Cerebral palsy (CP) is a group of disorders that affects an individual’s movement, balance, and/or posture. It is caused by differences in the brain that occur before, during, or after birth, in the early stages of brain development. Symptoms of cerebral palsy can vary greatly depending on which part of the brain is affected and the extent of the abnormality. Common symptoms include stiff or rigid muscles that can affect movement, posture, and one’s ability to speak; lack of muscle coordination; weak arms and/or legs; and an abnormal gait. In some cases, people with cerebral palsy have hypotonia, or decreased muscle tone, which causes muscles to be floppy. For instance, when an infant with decreased muscle tone in their neck is picked up, their head may flop to the side or backward or forward. People with cerebral palsy may also have other symptoms, including intellectual challenges, vision and/or hearing problems, seizures, and problems with other organ systems.

Cerebral palsy is the most common childhood physical disability. According to the Centers for Disease Control and Prevention (CDC), cerebral palsy affects an estimated 1 in 345 children in the United States. It more commonly occurs in males than females, and there is a greater chance of cerebral palsy in births of twins or other multiples, preterm births, and babies with a low birth weight.

While cerebral palsy is a lifelong condition with no cure, treatments, including physical, occupational, and speech therapy, medications, and surgery, can help manage symptoms and improve motor function.

“Cerebral palsy has a wide spectrum of involvement. People and families have varieties of goals for independence, inclusion, quality of life, and experience, and there is much the Yale team can do to help these goals become successful realities,” says David Frumberg, MD, an Associate Professor of Orthopaedics and Rehabilitation at the Yale School of Medicine and director of the Cerebral Palsy Lifespan Program at Yale New Haven Hospital.

Cerebral palsy refers to a group of neurological disorders that primarily affects movement, coordination, and posture. The condition results from an abnormality or injury to the brain that occurs before birth, during delivery and birth, or after birth, in the early developing brain.

The abnormalities or damage that causes cerebral palsy occur in parts of the brain involved in regulating movement and posture, and the symptoms an individual has are related to the area of the brain that is affected. The brain abnormalities and injuries that cause cerebral palsy are non-progressive, meaning they do not worsen as the person ages; however, the impact they have on a person may change over time.

There are four types of cerebral palsy:

• Spastic cerebral palsy. Accounting for around 80% of cerebral palsy cases, this type is characterized by stiff, weak muscles, as well as jerky and awkward movements of the affected limbs. Subtypes of spastic cerebral palsy include:
  • Spastic hemiplegic cerebral palsy affects only one side of the body. This type of cerebral palsy can result in scoliosis (curvature of the spine). In most cases, there is no cognitive impairment, though speech may be delayed.
  • Spastic diplegic cerebral palsy affects the legs more than the arms. The muscles in the legs may be tight, resulting in walking difficulties. When people with spastic diplegic cerebral palsy walk, their knees may bump into one another or cross (sometimes called scissoring). They may also walk on their toes. People with this type of cerebral palsy typically do not have speech delays or cognitive impairment.
  • Spastic quadriplegic cerebral palsy affects all four limbs. It is the most severe type of cerebral palsy. Most people with this type of cerebral palsy have some degree of cognitive impairment. The muscles in the arms and legs are typically stiff, while those in the neck may be floppy. Often, people with spastic quadriplegic cerebral palsy are unable to walk, have difficulties with speech and swallowing, and may have frequent seizures.
• Dyskinetic cerebral palsy. The second most common type of cerebral palsy, dyskinetic cerebral palsy accounts for around 15% of cases. In this form of cerebral palsy, the hands, arms, feet, and legs move slowly and involuntarily. The movement may be writhing or jerky and may increase during periods of excitement or stress. Intelligence is typically normal, though people with dyskinetic cerebral palsy often experience hearing problems, as well as speech and swallowing difficulties, abnormal gait, and drooling.
• Ataxic cerebral palsy. This rare type of cerebral palsy is characterized by problems with coordination, balance, and depth perception. People with ataxic cerebral palsy may have difficulties walking and may walk with their feet wide apart, and when reaching for objects, their movement may be shaky (known as an intention tremor). They may also have difficulty with fine motor skills, such as buttoning a shirt.
• Mixed types of cerebral palsy. In mixed types of cerebral palsy, people have symptoms of different types of the condition.

Cerebral palsy is caused by brain abnormalities or damage that occurs during brain development before or during birth, or during infancy.

Most cerebral palsy cases are caused by brain abnormalities or brain damage that occurs before birth, in the prenatal period. Some prenatal causes include:

• Infections during pregnancy, such as toxoplasmosis, rubella, cytomegalovirus (CMV), Zika virus, and herpes
• Fever during pregnancy
• Physical trauma to the pregnant person
• Exposure to toxins during pregnancy
• Rh incompatibility between the pregnant person and child. Rh factor is a protein found on the surface of red blood cells. People who have this protein are Rh-positive. People who do not have this protein are Rh-negative. Rh incompatibility occurs when the pregnant person is Rh-negative and the baby is Rh-positive.
• Fetal growth restriction, a condition in which the fetus does not grow as well as expected during pregnancy
• Multiple pregnancy (also called multiple gestation), being pregnant with more than one fetus (twins, triplets, etc.)
• Genetic abnormalities
• Congenital (present at birth) brain anomalies
• Antepartum (before birth) bleeding, which occurs when a pregnant person has any bleeding from their genitals at or after the 24^th week of pregnancy

Some causes of cerebral palsy during delivery and at birth include:

• Preterm birth (birth before 37 weeks of pregnancy) and/or low birth weight (under 5.5 pounds). The use of assisted reproductive technology (ART), such as in vitro fertilization (IVF), is associated with increased risk for cerebral palsy, in large part because it increases the chances of preterm birth or multiple pregnancies.
• Complications during labor or delivery that reduce the amount of oxygen delivered to the baby’s brain

Causes of cerebral palsy after birth may include:

• Infections, such as sepsis
• Meningitis, or inflammation of the membranes around the brain and spinal cord, often caused by an infection
• Stroke
• Intracranial hemorrhage
• Head injury
• Near-drowning or other events that cause cerebral hypoxia (when the brain does not get enough oxygen)
• Untreated jaundice

In about 80% of cases, the exact cause of cerebral palsy is unknown. However, current research suggests that a genetic abnormality may be the underlying cause of the condition.

In many cases, signs and symptoms of cerebral palsy become apparent in the first weeks or months of a baby’s life, though sometimes diagnosis is delayed until age 2 or later. These early indications typically include delays in reaching milestones, such as rolling over or sitting, abnormal muscle tone that makes them feel stiff or floppy, motor asymmetries, and problems with posture. Early diagnosis is key for earlier intervention.

Signs and symptoms of cerebral palsy in infants may include:

Age 3-6 months old:

• Head flops or falls backward when baby is picked up from a lying position
• When picked up, the baby’s legs stiffen and cross or “scissor”
• Baby feels floppy or stiff

Over 6 months old:

• Difficulty moving hands to their mouth
• Reaching with one hand while the other is fisted
• Unable to roll over on either side
• Unable to bring hands together

Over 10 months old:

• Lopsided crawling due to pushing and/or pulling with limbs on one side of the body while dragging the limbs on the other side of the body
• Scoots on buttocks or hops on knees (does not crawl on hands and knees)

In children and adults, symptoms may include:

• Spasticity (stiff or rigid muscles that may cause abnormal posture, exaggerated reflexes, repetitive jerky movements, leg crossing or scissoring, pain, joint deformity, and/or speech problems)
• Ataxia (lack of muscle coordination that can affect balance, speech, swallowing, and walking)
• Arm and/or leg weakness
• Muscle tone that is stiff or floppy
• Writhing, involuntary movements (known as athetosis)
• Hand tremors
• Drooling
• Difficulty swallowing
• Difficulty with speech
• Difficulty with fine motor control, such as buttoning a shirt
• Difficulty with walking, which may include walking on the toes, with scissored legs, or while crouched
• Joint problems, such as contractures (when muscles are fixed in a rigid position, making it difficult for the joint to function normally)

The following conditions or complications may affect people with cerebral palsy:

• Urologic conditions, including urinary incontinence, voiding dysfunction (difficulty emptying the bladder), and neurogenic bladder (a bladder control problem caused by a condition that affects the brain, spinal cord, or nerves)
• Constipation
• Intellectual disability
• Chronic pain
• Sleep disorders
• Hip dislocation, subluxation (partial dislocation), and dysplasia (when the bones in the hip do not develop properly resulting in joint instability and pain)
• Epilepsy or seizures
• Vision and/or hearing impairments
• Gastroesophageal reflux disease (GERD)
• Scoliosis
• Communication difficulties
• Poor growth
• Osteopenia (reduced bone density) or osteoporosis (more severe reduced bone density that increases the risk for bone fractures)

To diagnose cerebral palsy, doctors will review the child's medical history, conduct a physical exam, and order one or more diagnostic tests.

The doctor may ask questions about the child's prenatal and birth history, including whether there were any infections or complications during pregnancy, premature delivery, or low birth weight. The doctor may also ask about milestones in the child's development, such as when they began sitting, crawling, and walking, as well as any concerns about muscle tone, movements, and coordination. Additionally, the doctor might ask whether the child has a family history of cerebral palsy or other neurological disorders.

During the physical exam, the doctor will look for signs of cerebral palsy. This may involve observing how the child crawls, walks, sits, and moves, and checking for muscle tone, reflexes, and motor coordination. The doctor will also assess the child's posture and might look for muscle stiffness or floppiness, involuntary movements, and asymmetry in the use of limbs. The child's speech, vision, hearing, and intellectual development may also be evaluated.

Diagnostic tests can help doctors confirm the diagnosis, determine the cause of the disorder, and rule out other conditions. Diagnostic tests may include:

• Imaging tests:

• Magnetic resonance imaging (MRI). MRI scans help doctors identify abnormalities or damage in the brain tissue that might be causing the symptoms of cerebral palsy. MRI is the preferred imaging test for diagnosing cerebral palsy.
• Computed tomography (CT) scan. CT scans can provide information about brain structure that helps doctors identify any abnormalities.
• Cranial ultrasound. This type of ultrasound is often used in newborns and young infants. If any brain abnormalities are identified using cranial ultrasound, doctors will often perform a follow-up brain MRI.
• Electroencephalogram (EEG). While not used to diagnose cerebral palsy, an EEG measures electrical activity in the brain and may be used if a child has had seizures to rule out epilepsy or other disorders.
• Metabolic and genetic testing. Some genetic and metabolic disorders, such as Arginase deficiency, Lesch-Nyhan syndrome, and Angelman syndrome, among many others, can cause symptoms similar to those seen in cerebral palsy. A doctor may order metabolic and/or genetic testing to confirm cerebral palsy and to rule out other conditions. Metabolic testing requires bloodwork and/or a urine sample, and genetic testing is often done using a blood or saliva sample.

There are also physical and occupational therapists specifically trained to assess signs of cerebral palsy. Many evidence-based diagnostic measures exist, including the Hammersmith Infant Neurological Exam (HINE), a neurological assessment for children between 2 months and 2 years of age. Referral to a therapist trained in the screening for cerebral palsy risk factors frequently assists in making a timely diagnosis.

Treatments for cerebral palsy include:

• Physical therapy. This treatment focuses on improving strength, flexibility, balance, motor function, and mobility through exercises and activities. It helps manage spasticity and can prevent complications such as contractures, hip disorders, and scoliosis.
• Occupational therapy. Occupational therapists work to enhance the individual's ability to perform daily tasks and self-care, such as dressing, eating, bathing, and using the toilet, by developing fine motor skills.
• Speech and language therapy. This therapy addresses difficulties with speech, communication, and swallowing. People may learn sign language and other methods of communication, such as using speech-generating devices.
• Orthotics and other devices: These include braces, splints, and other supportive devices, such as crutches, wheelchairs, or scooters, that can help improve posture, gait, balance, and mobility.
• Medications. These are used to manage symptoms, such as muscle stiffness, spasticity, seizures, and pain, among others. Common medications include:
• Chemodenervation, to decrease muscle tone of specific muscles to reduce spasticity. This is frequently done with Botulinum toxin or other medications. Injections are typically given every three to eight months.
• Oral anti-spasticity medications, such as baclofen (a muscle relaxant), or benzodiazepines, which reduce spasticity.
• Intrathecal baclofen pumps, which are devices surgically implanted in the abdomen. Baclofen, a skeletal muscle relaxant, is continuously administered to the fluid surrounding the spinal cord via a tube. Baclofen pumps may be used for people with severe spasticity who do not respond well to oral anti-spasticity drugs.
• Different types of medications may also be used to treat other symptoms, such as seizures, incontinence, low bone density, and chronic pain.
• Surgery. Surgery might be recommended to correct anatomical abnormalities or release tight muscles and tendons. Surgical treatments for cerebral palsy include:
• Selective dorsal rhizotomy (SDR), a neurosurgical procedure in which the nerve roots contributing most to spasticity are divided at the base of the spinal column. The treatment can permanently reduce spasticity and pain.
• Orthopedic surgical procedures, which are performed to treat problems with muscles, joints, and bones. This may include surgery to treat hip disorders, contractures, limb position, and scoliosis.
• Surgery, which may also be used to treat GERD, drooling, voiding dysfunction (difficulty emptying the bladder), and other problems.
  

The outlook for people with cerebral palsy can vary widely depending on several factors, including the severity of their condition, the type of cerebral palsy, and whether they develop any associated conditions or complications. The individual's response to treatment also plays a critical role in shaping their long-term outlook. Early intervention and tailored therapies can help individuals function with greater independence, reduce the degree of disability, and improve quality of life. Because cerebral palsy affects each person differently, the outlook can be highly individualized.

Overall, while cerebral palsy is a lifelong condition, with support and treatment, most people attend school, participate in work, and engage in social activities. For others, however, the condition causes more severe symptoms, requiring daily assistance and care.

“At Yale Medicine, we are dedicated to treating cerebral palsy across the entire lifespan, ensuring that our patients receive consistent and comprehensive care from childhood through adulthood,” says Jennifer Hankenson, MD, a Yale Medicine physiatrist (a doctor who specializes in physical medicine and rehabilitation). “Our approach is focused on maximizing function at every stage of life. In physiatry, we utilize emerging nonoperative therapies to manage muscle tone and spasticity, providing innovative treatments that adapt as our patients' needs change over time. This lifelong commitment to our patients ensures that they achieve and maintain the highest possible quality of life.”