Brown-Séquard syndrome (BSS) is a rare and treatable condition that happens when damage to your spinal cord causes weakness or paralysis on one side of your body and a loss of sensation on the other side.
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Brown-Séquard syndrome (BSS) is a rare neurological condition that happens when damage to your spinal cord causes muscle weakness or paralysis on one side of your body and a loss of sensation on the opposite side. The damage occurs on only one side of your spinal cord in a specific area.
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Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy
Your spinal cord is a cylindrical structure that runs through the center of your spine, from your brainstem to your low back. It's a delicate structure that contains nerve bundles and cells that carry messages from your brain to the rest of your body and vice versa. Your spinal cord is one of the main parts of your nervous system.
Brown-Séquard syndrome is considered an incomplete spinal cord injury (SCI), meaning there’s partial preservation of sensory function, motor function or a combination of both below where the injury occurred on your spinal cord. A complete SCI results in the loss of all sensory and voluntary motor functions below the level of the injury.
BSS has several possible causes, but the most common cause is trauma — typically penetrating trauma such as a gunshot or stab wound. Inflammation or pinching of your spinal cord can also cause BSS occasionally.
Brown-Séquard syndrome is named after scientist Charles-Édouard Brown-Séquard, who first described it in 1849.
Central cord syndrome (CCS) and Brown-Séquard syndrome (BSS) are both incomplete spinal cord injuries, but they’re distinct conditions.
CCS is an incomplete traumatic injury to the center of your spinal cord, usually in your neck. This injury results in weakness in your arms that is worse than in your legs.
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BSS results from an incomplete spinal cord injury anywhere along your spine, and it causes weakness or paralysis on one side of your body and a loss of sensation on the other side below where the injury is.
Brown-Séquard syndrome can affect anyone, though it’s a rare condition. It affects people assigned female at birth and people assigned male at birth in equal numbers.
Brown-Séquard syndrome is a rare condition.
Approximately 12,000 new cases of traumatic spinal cord injuries happen each year in the United States, and Brown-Séquard syndrome is estimated to result from 2% to 4% of these cases.
Symptoms of Brown-Séquard syndrome (BSS) usually appear after you experience spinal cord injury that causes damage on only one side of your spinal cord in a specific area anywhere along your spine.
The first symptoms of BSS are usually:
For example, if someone had Brown-Séquard syndrome due to an injury that affected the right side of their spinal cord in their middle back, they would have a loss of muscle movement on the right side of their body from the middle of their back and down, which would affect their right hip, leg and foot. They would have a loss of pain and temperature sensation (but still have muscle control) on the left side of their body from their middle back and down. Their head, neck, shoulders and arms would be unaffected by the spinal cord damage and would function as they normally do.
BSS can also cause the following symptoms:
The symptoms of BSS can vary from mild to severe. They generally improve with proper treatment of BSS.
If the cause of Brown-Séquard syndrome (BSS) is a traumatic event, such as a gunshot wound or vehicle collision, that event will cause pain. But the syndrome itself (the spinal cord injury) may not cause pain.
Some people with BSS may experience abnormal sensations (dysesthesia), such as a painful burning, prickling or aching feeling, due to the spinal cord injury.
The most common causes of Brown-Séquard syndrome (BSS) are traumatic injuries affecting your spinal cord, including:
If you experience any of these traumatic injuries, it’s important to get to the nearest hospital as soon as possible and receive immediate medical care.
There are several other less common causes of BSS that are due to non-traumatic conditions, including:
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If your healthcare provider suspects you may have Brown-Séquard syndrome (BSS), they’ll:
Your provider will then order certain tests, such as an MRI scan, to confirm the diagnosis or rule out other possible causes of your symptoms.
If your healthcare provider suspects you may have Brown-Séquard syndrome (BSS), they’ll likely order the following tests:
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The treatment for Brown-Séquard syndrome (BSS) depends on the underlying cause of the spinal cord damage.
In general, the treatment goals for Brown-Séquard syndrome include:
People who have BSS as the result of a penetrating injury will need to be treated for bleeding and direct tissue damage. Similarly, people with BSS who have other injuries from the trauma that caused BSS will need additional treatment for those injuries.
There are two general phases of treatment for BSS, including initial treatment and rehabilitation.
General therapies for initial treatment of BSS may include:
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After initial care for Brown-Séquard syndrome (BSS), rehabilitation in the form of physical and occupational therapy should begin as soon as possible to improve and/or regain motor function.
Physical therapy goals include:
Physical therapy involves therapies and exercises to ease pain and help you function and move. Your physical therapist will work with you to improve your mobility. They may provide devices that help you continue daily activities, such as braces, hand splits, limb supports or a wheelchair.
Occupational therapy involves therapies and exercises that help people regain independence in all areas of their lives after a physical or neurological issue. During occupational therapy for BSS, you’ll learn new techniques, with or without the use of adaptive equipment, for everyday tasks, such as hygiene and grooming, eating and putting on clothes.
The only way to prevent Brown-Séquard syndrome is to practice standard safety, such as driving and traffic safety, to try to prevent injuring your spinal cord.
The prognosis (outlook) of Brown-Séquard syndrome (BSS) depends on several factors, including the cause of the spinal cord damage and how much it’s damaged.
But, overall, the prognosis of BSS is usually good. People with BSS have a fair chance of recovering some of their function, including walking. Recovery is a slow process, however. It becomes slower throughout three to six months after the onset of the syndrome, and it can take up to two years for ongoing neurological recovery.
Untreated Brown-Séquard syndrome may result in the following complications:
If you experience sudden muscle weakness or paralysis and/or loss of sensation on one side of your body, get to the nearest emergency room as soon as possible.
If you’ve been diagnosed with Brown-Séquard syndrome, you’ll need to see your healthcare team regularly to make sure your spinal cord injury is healing properly. Be sure to go to all of your physical and occupational therapy appointments to ensure the best and quickest recovery possible.
A note from Cleveland Clinic
Brown-Séquard syndrome can be scary to experience. The good news is that many people with this condition regain or have improved motor and sensory function after several months of recovery. Know that your healthcare team will be available to help you get back on track.
Last reviewed on 04/11/2022.
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