Hemiplegia Explained: Causes, Types, Symptoms, and Outlook

Author: Thomas C. Weiss
Published: 24 Jan 2012 - Updated: 30 Sep 2026
Publication Type: Informative

Table of Contents:
Synopsis - Definition - Overview - FAQs - Insights, Updates - Related Content

Synopsis

This information explains hemiplegia, a loss of motor function on one side of the body that is most often caused by damage to the brain hemisphere opposite the affected side. It covers the main forms of the condition: hemiplegia after a stroke, which often affects the face, arm, and leg together; alternating hemiplegia, a rare childhood neurological disorder with recurring episodes of paralysis; and childhood hemiplegia, which can be congenital or acquired. It affects stroke survivors, children with brain injuries from before, during, or after birth, and the parents, caregivers, and clinicians who support them. The content is useful because it sets out the causes, typical symptoms, and likely outcomes in plain terms, which helps families recognize early signs such as developmental delays and one-sided stiffness, and helps adults living with the condition, along with seniors at higher risk of stroke, understand what the diagnosis means for daily movement and independence.*

At a Glance

• 1 - Episodes of alternating hemiplegia often resolve after the child sleeps.
• 2 - Childhood hemiplegia is relatively common, affecting up to one child in every 1,000.
• 3 - Alternating hemiplegia usually appears before 18 months of age. Children may also show stiffening or dance-like limb movements along with balance problems.
• 4 - Some children with a family history of alternating hemiplegia carry mutations in the CACNA1A, SCN1A, or ATP1A2 genes. The ATP1A2 gene has also been linked to familial hemiplegic migraine.

Topic Definition

Hemiplegia

Hemiplegia is severe or complete paralysis of the muscles on one side of the body, usually affecting the arm, leg, and sometimes the face on that side. It most often results from damage to the brain hemisphere opposite the paralyzed side, such as from a stroke, traumatic brain injury, or brain injury that happens before, during, or shortly after birth. Less often, it can stem from brain stem lesions, cervical spinal cord disease, or peripheral nerve disorders. The term comes from the Greek word hemi, meaning half, and the condition is related to but more severe than hemiparesis, which describes one-sided weakness rather than full loss of movement.

Overview

Hemiplegia is the inability to move a group of muscles in one side of the body. When hemiplegia is caused by a stroke, it often involves muscles in the face, arms and legs. Hemiplegia results in severe or complete loss of motor function on one side of the body; this condition is usually caused by brain diseases that are localized to the cerebral hemisphere opposite to the side of weakness; less frequently, brain stem lesions; cervical spinal cord diseases, peripheral nervous system diseases, and other conditions may manifest as hemiplegia.

Alternating Hemiplegia

Alternating hemiplegia is a rare neurological disorder that develops in childhood, most often before the child is 18 months old. The disorder is characterized by recurrent episodes of paralysis that involve one or both sides of the body, multiple limbs, or a single limb.

The paralysis may affect different parts of the body at different times and may be brief or last for several days. Oftentimes these episodes will resolve after sleep. Affected children may also have abnormal movements involving stiffening or "dance-like" movements of a limb, as well as walking and balance problems. Some children have seizures.

Children may have normal or delayed development. There are both benign and more serious forms of the disorder. Most children do not have a family history of the disorder; however, recent studies have show that some children with a family history have mutations in the genes CACNA1A, SCN1A, and ATP1A2. Mutations in the ATP1A2 gene have previously been associated with families affect by familial hemiplegic migraine.

Childhood Hemiplegia

Childhood hemiplegia (sometimes called hemiparesis) is a condition affecting one side of the body. We talk about a right or left hemiplegia, depending on the side affected. It is caused by damage to a part of the brain, which may happen before, during or soon after birth, when it is known as congenital hemiplegia, or later in childhood, in which case it is called acquired hemiplegia

Generally, injury to the left side of the brain will cause a right hemiplegia and injury to the right side a left hemiplegia. Childhood hemiplegia is a relatively common condition, affecting up to one child in 1,000. The symptoms of Spastic Hemiplegic Cerebral Palsy may differ from child to child and over time. Symptoms may include:

• Seizures.
• Difficulty with walking and balance.
• Difficulty with fine motor tasks like writing or using scissors.
• Stiffness and weakness in muscles on one side of the body.
• About one fourth of children with spastic hemiplegia may have an IQ below 70.
• Delay in reaching expected developmental milestones such as rolling over, sitting up, crawling, or smiling.

Children with the benign form of alternating hemiplegia have a good prognosis. Those who experience the more severe form have a poor prognosis because intellectual and mental capacities do not respond to drug therapy, and balance and gait problems continue. Over time, walking unassisted becomes difficult or impossible.

Frequently Asked Questions

NOTE: Researched FAQs by Disabled World (DW)

What is the difference between hemiplegia and hemiparesis?

Hemiplegia refers to complete or near complete paralysis on one side of the body, while hemiparesis describes weakness on one side without full loss of movement. The two terms are often used interchangeably in childhood cases, but hemiparesis is generally the milder form.

How is hemiplegia diagnosed?

Doctors usually begin with a physical and neurological exam to check strength, reflexes, and coordination. Brain imaging such as MRI or CT scans is then used to locate the injury, and genetic testing may be ordered when alternating hemiplegia is suspected.

Can a person recover from hemiplegia after a stroke?

Many people regain some movement, especially when rehabilitation starts early and continues consistently. The brain can form new pathways through neuroplasticity, and the greatest gains often occur within the first several months after the stroke.

What therapies are used to treat hemiplegia?

Treatment commonly includes physical therapy, occupational therapy, and speech therapy when needed. Approaches such as constraint induced movement therapy, electrical stimulation, and task based training help strengthen the affected side and improve daily function.

How is muscle stiffness from hemiplegia managed?

Spasticity can be eased with regular stretching, splints or braces, and oral medications such as baclofen. Botulinum toxin injections are often used to relax specific tight muscles and make therapy more effective.

What assistive devices help people living with hemiplegia?

Useful aids include canes, quad canes, walkers, ankle foot orthoses, and wheelchairs for mobility. One handed kitchen tools, button hooks, grab bars, and adapted computer keyboards can make daily tasks easier and safer.

Can people with hemiplegia drive a car?

Many people with hemiplegia can drive after a formal driving assessment and with vehicle modifications. Common adaptations include a steering knob, a left foot accelerator, and hand controls, depending on which side of the body is affected.

Which gene is most often linked to alternating hemiplegia of childhood?

Mutations in the ATP1A3 gene are found in the majority of children with alternating hemiplegia of childhood. Most of these mutations are new changes that were not inherited from either parent.

Insights, Analysis, and Developments

Editorial Note: Hemiplegia is not one single condition but a pattern of one-sided weakness or paralysis that can come from many sources, including stroke, brain injury around the time of birth, rare genetic disorders, and diseases of the brain stem or spinal cord. That variety is why outcomes differ so much from person to person. A child with the benign form of alternating hemiplegia can do well, while the more severe form may lead to lasting balance, gait, and cognitive challenges that do not respond to medication. For adults and older people, stroke remains the leading cause, and the side of the body affected points directly to where the brain was injured. Knowing these patterns helps families push for early assessment, therapy, and support, since early action tends to shape how much independence and function a person keeps over time.*

Author Credentials: Thomas C. Weiss is a researcher and editor for Disabled World. Thomas attended college and university courses earning a Masters, Bachelors and two Associate degrees, as well as pursuing Disability Studies. As a CNA Thomas has provided care for people with all forms of disabilities. Explore Thomas' complete biography for comprehensive insights into his background, expertise, and accomplishments.

* Editorial additions by Ian C. Langtree.