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Lee, DO — By Lauren Hellicar on September 27, 2022A person may experience hemiparesis, or one-sided weakness, following a stroke or another condition, such as a brain tumor. It can affect a range of different body parts, including the hands and feet. Specifically, the stroke may cause weakness in the right side of the brain or the left side of the brain. This may depend on the part of the brain where the stroke occurred. Hemiparesis can make it difficult for a person to carry out their daily activities, such as eating, dressing, or walking. However, there are some possible treatments for hemiparesis, which can involve electrical stimulation of the brain or body parts, that can help restore strength and movement. Read on to learn more about hemiparesis, including a range of actions a person can take to support recovery from this condition. What is hemiparesis Share on Pinterestadamkaz/Getty ImagesHemiparesis means one-sided weakness. Around 65% of people who have had a stroke experience hemiparesis. It can happen on one side, unilateral hemiparesis, or on both sides, diplegic or paraplegic hemiparesis, of the body. The part, or parts, of the body affected by hemiparesis depends on the part of the brain affected by the stroke. The left side of the brain controls language and speech. Injuring the left side of the brain can cause weakness on the right side of the body. The right side of the brain controls nonverbal communication and some behaviors. Injuring the right side of the brain can cause weakness on the left side of the body. Types Some forms of hemiparesis include: Ipsilateral hemiparesis Some people experience weakness on the same side of the body as the side of the brain that was affected by the stroke. This is known as ipsilateral hemiparesis. A 2017 study, involving 8,360 people, concluded that most people with ipsilateral hemiparesis had previously had a stroke on the other side of the brain to their recent stroke. This caused mobility difficulties on the opposite side of the body to the brain injury caused by the earlier stroke. Ataxic hemiparesis Ataxia occurs when a person has trouble coordinating their voluntary muscle movements. In ataxic hemiparesis, this difficulty presents on one side of the body. Ataxia has a number of possible causes, and it can develop gradually or suddenly. When a stroke causes ataxic hemiparesis, for instance, it tends to strike suddenly and progress quickly, with potentially serious consequences. Spastic hemiparesis Spasticity refers to the condition where a person has atypical levels of muscle stiffness or tone. For example, approximately 80% of people with cerebral palsy may experience spasticity. Spastic hemiparesis means having an abnormal level of muscle stiffness on one side of the body. It usually affects a person’s arm more than their leg. Hemiparesis vs hemiplegia Hemiparesis is different than hemiplegia. Following a stroke, a person can develop either condition. While hemiparesis causes muscle weakness, hemiplegia causes total loss of muscle function. Loss of muscle function is also called paralysis. Learn more about paralysis here. Causes Stroke commonly causes hemiparesis. During a stroke, some parts of the brain do not receive enough oxygen, which can lead to the death of brain cells. If oxygen does not reach the part of the brain that controls movement and strength, it causes hemiparesis. However, people with other conditions can experience hemiparesis. These may include: brain injurybrain tumorcerebral palsymultiple sclerosis Learn more about stroke here. Symptoms The one-sided weakness a person with hemiparesis experiences may affect their arms, hands, face, chest, legs, or feet. This can have one or more of the following effects on a person:loss of balancedifficulty walkingdifficulty grasping objectsdecreased movement precisionmuscle fatiguelack of coordination Diagnosis Hemiparesis is commonly a symptom of stroke. Doctors take computed tomography (CT) images of the brain and its associated blood vessels to diagnose a person. Specifically, CT angiography involves injecting a special dye into the brain and taking a CT scan of its blood vessels and tissues. A doctor may also use an MRI scan when stroke is suspected to detect any restricted blood flow to the brain. According to older research from 2007, MRIs are considered more accurate at detecting stroke than CT. Additionally, older research from 2016 found that testing a person’s muscle strength in their hands and feet may be a reliable way to assess a person with long-term hemiparesis following a stroke. Treatment A range of rehabilitation therapies are available for the treatment of hemiparesis: Modified constraint-induced therapy mCIT This is an effective treatment to enhance upper limb function in people following a stroke. Upper limb dysfunction can have a profound effect on day-to-day activities. This therapy type focuses on helping limit use of the upper limbs on the unaffected side of the body, thus promoting the use of the more affected limbs. The unaffected upper limbs may need restraining, such as using slings or mitts. It typically involves repeated, concentrated training. Other therapies, such as mental imagery, may be used to enhance mCIT. However, further research into the longer-term effects of mCIT is needed. Mental imagery Both mental visualization and physical movement activate similar overlapping areas of the brain. This can mean that if a person imagines moving the weakened part of their body, it may activate muscles and the areas of the brain that they would use if they were actually doing the movement. Combining mental imagery with other therapies can be beneficial in improving impairment and upper extremity activity in people with hemiparesis. Electrical stimulation Electrical stimulation involves placing small electrical pads on a person’s weakened muscles. This treatment delivers an electrical shock to the muscle, which encourages contraction. The shock may either feel like a burning sensation or a mild tingling, depending on the shock intensity. Improved movement and motor control are benefits of this treatment. Cortical stimulation Doctors place a tiny electrode on the dura, which is the membrane covering the brain, of a person receiving cortical stimulation. While the person participates in rehabilitation exercises, the electrode sends an electrical current to the brain. However, older research from 2016 — specifically the Everest phase III trial — looking into the effectiveness of cortical stimulation in helping a person regain hand motor skills has not been conclusive. The researchers found that 24 weeks after rehabilitation, the participants who underwent cortical stimulation showed functional improvements when compared with the control group. Still, they urged caution in interpreting the results because the improvements may have been in part due to the cortical stimulation group receiving more attention from the researchers — a scientific phenomenon known as the “Hawthorne effect.” Assistive devices The American Stroke Association (ASA) suggests speaking with a physical therapist, who can recommend an appropriate device to help improve strength and movement in a person with hemiparesis. Devices include:braces, such as an ankle-foot bracecaneswalkers, or a walking aid with four points of contact with the groundwheelchairs Practicing regularly with an assistive device can help a person improve managing their movements and flexibility, and support repairing damaged nerves. A person should work with a healthcare professional to develop a plan that includes appropriate exercises. Living with hemiparesis The ASA also suggests a range of home and lifestyle modifications a person with hemiparesis can make to help with improving their motor skills. Home modifications to help make life easier include:raising the toilet seatinstalling a bench in the bathtub, with adhesive strips on the bottom of the tubpurchasing an electric toothbrush and razor if requiredinstalling grab bars and ramps wherever helpful in the home Lifestyle changes to help speed up recovery and prevent falls include:staying active to strengthen muscles and improve balancewearing flat, wide-toed shoes to help with balanceusing one of the prescribed assistive devices mentioned above rather than grabbing onto furniture for supportavoiding activities that become unsafe when taking medicines that cause drowsinessbeing mindful while walking to avoid falling Summary Hemiparesis means one-sided weakness. Symptoms include loss of balance and lack of coordination. A stroke or another type of brain trauma can cause hemiparesis. Treatments range from electrical stimulation to using assistive devices. A range of lifestyle and home modifications can also support a person’s recovery. Last medically reviewed on September 27, 2022Public HealthStrokeRehabilitation / Physical Therapy 18 sourcescollapsedMedical News Today has strict sourcing guidelines and draws only from peer-reviewed studies, academic research institutions, and medical journals and associations. We avoid using tertiary references. We link primary sources — including studies, scientific references, and statistics — within each article and also list them in the resources section at the bottom of our articles. You can learn more about how we ensure our content is accurate and current by reading our editorial policy.Amidei, C., et al. (2015). Clinical implications of motor deficits related to brain tumors.https://academic.oup.com/nop/article/2/4/179/2459934Ashizawa, T., et al. (2016). Ataxia.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5567218/Barclay, R. E., et al. (2020). Mental practice for treating upper extremity deficits in individuals with hemiparesis after stroke.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7387111/Cao, M., et al. (2021). Effectiveness of modified constrain-induced movement therapy for upper limb function intervention following stroke: A brief review.https://www.sciencedirect.com/science/article/pii/S2666337621000433Bindawas, S. M., et al. (2017). Functional recovery differences after stroke rehabilitation in patients with uni- or bilateral hemiparesis.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5946362/Dadlani, R., et al. (2018). Fluctuating hemiparesis as a result of traumatic brain injury-associated hyponatremia.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6050759/Functional electrical stimulation. (2019).https://www.stroke.org/en/about-stroke/effects-of-stroke/physical-effects-of-stroke/physical-impact/functional-electrical-stimulationHemiparesis. (2019).https://www.stroke.org/en/about-stroke/effects-of-stroke/physical-effects-of-stroke/physical-impact/hemiparesisInatomi, Y., et al. (2017). Ipsilateral hemiparesis in ischemic stroke patients.https://pubmed.ncbi.nlm.nih.gov/27666559/Levy, R. M., et al. (2015). Epidural electrical stimulation for stroke rehabilitation: Results of the prospective, multicenter, randomized, single-blinded Everest trial.https://journals.sagepub.com/doi/10.1177/1545968315575613Musuka, T. D., et al. (2015). Diagnosis and management of acute ischemic stroke: speed is critical.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4562827/Paralysis. (2016).https://medlineplus.gov/paralysis.htmlPark, J. H. (2015). The effects of modified constraint-induced therapy combined with mental practice on patients with chronic stroke.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4483446/Rabelo, M., et al. (2016). Reliability of muscle strength assessment in chronic post-stroke hemiparesis: a systematic review and meta-analysis [Abstract].https://pubmed.ncbi.nlm.nih.gov/26243549/Spasticity. (2022).https://www.ninds.nih.gov/health-information/disorders/spasticityThadchanamoorthy, V., et al. (2021). Early-onset multiple sclerosis with frequent relapses: A challenging diagnosis with a less favorable prognosis.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8052520/Walling, A.D. (2007). MRI is more appropriate for initial evaluation of stroke.https://www.aafp.org/pubs/afp/issues/2007/0815/p579.htmlWhat is cerebral palsy. (2022).https://www.cdc.gov/ncbddd/cp/facts.htmlFEEDBACK:Medically reviewed by Susan W. Lee, DO — By Lauren Hellicar on September 27, 2022 Latest newsWhat sets 'SuperAgers' apart? 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