Brown-Séquard Syndrome

Brown-Séquard syndrome (BSS) is a rare neurologic injury that causes hemisection of the spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord, resulting in weakness and paralysis of one side of the body and sensory loss on the opposite side. This syndrome is most often due to trauma, but it may also occur with disc herniation, hematoma, or tumor. Clinical presentation is consistent with ipsilateral damage to the corticospinal tracts and posterior columns (weakness, loss of proprioception, and vibration sensation) below the level of the lesion, and contralateral anterior column symptoms owing to the unilateral involvement of the spinothalamic tract (loss of pain Pain Pain has accompanied humans since they first existed, first lamented as the curse of existence and later understood as an adaptive mechanism that ensures survival. Pain is the most common symptomatic complaint and the main reason why people seek medical care. Physiology of Pain and temperature sensation). Diagnosis is confirmed with MRI. Management depends on the etiology and site of injury, and timely intervention is associated with a favorable prognosis and recovery.

Last update:

Editorial responsibility: Stanley Oiseth, Lindsay Jones, Evelin Maza

Table of Contents

Share this concept:

Share on facebook
Share on twitter
Share on linkedin
Share on reddit
Share on email
Share on whatsapp

Overview

Definition

Brown-Séquard syndrome (BSS) is a rare neurologic injury that causes hemisection of the spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord, resulting in weakness and paralysis of one side of the body and sensory loss on the opposite side. 

Epidemiology

  • Rare: 2%–4% of spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord injuries 
  • Incidence: higher in males
  • Average age at occurrence: 40 years

Anatomy

  • In a cross-sectional view, the spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord (SC) shows white matter surrounding gray matter. 
  • The gray matter is arranged in an H-shaped pattern. 
  • Gray matter: 
    • Anterior horn 
    • Posterior horn 
    • Lateral horn 
  • White matter: ascending and descending tracts in the peripheral SC
    • Anterolateral/ventral columns contain:
      • Anterior corticospinal tract 
      • Medial longitudinal fasciculus 
      • Lateral spinothalamic tract 
      • Anterior spinothalamic tract 
    • Lateral columns:
      • Lateral corticospinal tract 
      • Corticorubral/rubrospinal tract 
      • Spinocerebellar tract  
    • Dorsal columns:
      • Fasciculus gracilis
      • Fasciculus cuneatus

Etiology

The most frequent cause of BSS is penetrating injury. There are nontraumatic causes as well.

  • Traumatic causes: 
    • Knife/stab injury to the cervical region 
    • Gunshot/bullet to the spine 
    • Motor vehicle accident 
    • Fall resulting in vertebral fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures
  • Nontraumatic causes: 
    • Multiple sclerosis Multiple Sclerosis Multiple sclerosis (MS) is a chronic inflammatory autoimmune disease that leads to demyelination of the nerves in the CNS. Young women are more predominantly affected by this most common demyelinating condition. Multiple Sclerosis/demyelination
    • Herniation of the vertebral disc
    • Primary or metastatic tumors 
    • Spinal epidural hematoma 
    • Transverse myelitis 
    • Infections:
      • TB TB Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis complex bacteria. The bacteria usually attack the lungs but can also damage other parts of the body. Approximately 30% of people around the world are infected with this pathogen, with the majority harboring a latent infection. Tuberculosis spreads through the air when a person with active pulmonary infection coughs or sneezes. Tuberculosis 
      • Meningitis Meningitis Meningitis is inflammation of the meninges, the protective membranes of the brain, and spinal cord. The causes of meningitis are varied, with the most common being bacterial or viral infection. The classic presentation of meningitis is a triad of fever, altered mental status, and nuchal rigidity. Meningitis 
      • Syphilis Syphilis Syphilis is a bacterial infection caused by the spirochete Treponema pallidum pallidum (T. p. pallidum), which is usually spread through sexual contact. Syphilis has 4 clinical stages: primary, secondary, latent, and tertiary. Syphilis 

Pathophysiology

  • Ascending and descending tracts on one side of the spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord are damaged →
    • Petechial hemorrhages develop in the gray matter within an hour after injury → 
    • White matter is affected within 3–4 hours after injury.
  • 24–36 hours after injury → hemorrhagic necrosis → extensive damage in the myelinated fibers and long tracts 
  • Discontinuity in the primary somatosensory cortex and the supplementary motor area → clinically decreased sensation

Clinical Presentation and Diagnosis

Brown-Séquard syndrome occurs with hemisection of the spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord after an injury or other pathology. The neurologic findings on exam are related to the level of the spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord lesion.

Clinical presentation

  • Sensory loss: 
    • Ipsilateral loss of proprioception and vibratory sensation (dorsal columns) occurs below the level of the lesion (see image).
    • Contralateral loss of pain Pain Pain has accompanied humans since they first existed, first lamented as the curse of existence and later understood as an adaptive mechanism that ensures survival. Pain is the most common symptomatic complaint and the main reason why people seek medical care. Physiology of Pain and temperature sensations = spinothalamic tract (STT) beginning approximately 2 levels below the level of the lesion, since the STT continues on the ipsilateral side of the cord before crossing over to the contralateral side
  • Motor loss: ipsilateral loss of motor function below the level of the lesion (corticospinal tracts)
  • Autonomic intact: Unilateral involvement of the descending autonomic fibers does not produce bladder symptoms. 
  • In actuality, most cases of BSS are partial hemisections → varying degrees of sensory and motor loss depending on the etiology
  • Ipsilateral Horner sign (loss of sympathetic input) if lesion is above T1:
    • Miosis (constricted pupil Pupil The pupil is the space within the eye that permits light to project onto the retina. Anatomically located in front of the lens, the pupil's size is controlled by the surrounding iris. The pupil provides insight into the function of the central and autonomic nervous systems. Physiology and Abnormalities of the Pupil)
    • Ptosis (droopy eyelid)
    • Anhidrosis (loss of sweating)
Site of clinical presentation in brown-séquard syndrome

Image representing the clinical findings in Brown-Séquard syndrome:
The green area represents the side of the spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord lesion (right side).
1: Level of the lesion
2: Ipsilateral loss of proprioception and vibratory sensation occurs below the level of the lesion (dorsal columns) and motor function (corticospinal tract).
3: Contralateral loss of pain Pain Pain has accompanied humans since they first existed, first lamented as the curse of existence and later understood as an adaptive mechanism that ensures survival. Pain is the most common symptomatic complaint and the main reason why people seek medical care. Physiology of Pain and temperature sensation occurs beginning approximately 2 levels below the level of the lesion (spinothalamic tract).

Image by Lecturio.

Diagnosis

  • History and physical exam: 
    • To determine the cause/extent of the damage and neurologic deficits 
    • If the lesion is above T1, Horner syndrome Horner syndrome Horner syndrome is a condition resulting from an interruption of the sympathetic innervation of the eyes. The syndrome is usually idiopathic but can be directly caused by head and neck trauma, cerebrovascular disease, or a tumor of the CNS. Horner Syndrome is seen.
    • Travel history is also essential to rule out infections. 
  • Laboratory analysis: 
    • Testing to rule out infectious etiologies, if indicated
    • Consider TB TB Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis complex bacteria. The bacteria usually attack the lungs but can also damage other parts of the body. Approximately 30% of people around the world are infected with this pathogen, with the majority harboring a latent infection. Tuberculosis spreads through the air when a person with active pulmonary infection coughs or sneezes. Tuberculosis as a cause of BSS, if applicable.
  • Imaging: 
    • Plain films are obtained in cases of acute trauma. 
    • MRI is the gold standard. 
    • CT myelography is done if MRI is contraindicated.
    • Angiography to determine vascular malformations 

Management

Treatment of BSS depends on the etiology and site of injury. Complications are mainly due to penetrating trauma wounds, in untreated cases, or with late intervention. Prognosis in BSS is good as compared with other spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord syndromes owing to its incomplete involvement of the SC.  

Treatment

  • Wound debridement
  • Pharmacotherapy:
    • Tetanus Tetanus Tetanus is a bacterial infection caused by Clostridium tetani, a gram-positive obligate anaerobic bacterium commonly found in soil that enters the body through a contaminated wound. C. tetani produces a neurotoxin that blocks the release of inhibitory neurotransmitters and causes prolonged tonic muscle contractions. Tetanus vaccine Vaccine A vaccine is usually an antigenic, non-virulent form of a normally virulent microorganism. Vaccinations are a form of primary prevention and are the most effective form due to their safety, efficacy, low cost, and easy access. Vaccination in the presence of a wound
    • Antibiotics to prevent infection (with penetrating trauma)
    • Pain management Pain Management Pain is defined as an unpleasant sensory and emotional experience associated with actual or potential tissue damage. Pain is a subjective experience. Acute pain lasts < 3 months and typically has a specific, identifiable cause. Pain Management with analgesics
    • Baclofen for muscle spasticity 
  • Physical therapy:
    • Maintain strength of neurologically intact muscles 
    • Prevent damage to joints and maintain their range of motion
    • Prevent decubitus ulcers
    • Promote mobilization or device-assisted ambulation 
    • Establishing a routine for daily activities
  • Surgery:
    • Indications: BSS due to trauma accompanied by:
      • CSF leakage 
      • Retention of foreign bodies 
      • Cord compression  
    • Procedures:
      • Spinal reduction, destabilization, and decompression 
      • Dural repair
  • Spine immobilization

Complications

  • Hypotension Hypotension Hypotension is defined as low blood pressure, specifically < 90/60 mm Hg, and is most commonly a physiologic response. Hypotension may be mild, serious, or life threatening, depending on the cause. Hypotension 
  • Spinal shock Shock Shock is a life-threatening condition associated with impaired circulation that results in tissue hypoxia. The different types of shock are based on the underlying cause: distributive (↑ cardiac output (CO), ↓ systemic vascular resistance (SVR)), cardiogenic (↓ CO, ↑ SVR), hypovolemic (↓ CO, ↑ SVR), obstructive (↓ CO), and mixed. Types of Shock: after acute trauma → motor paralysis with initial loss but gradual recovery of reflexes (not neurogenic shock Shock Shock is a life-threatening condition associated with impaired circulation that results in tissue hypoxia. The different types of shock are based on the underlying cause: distributive (↑ cardiac output (CO), ↓ systemic vascular resistance (SVR)), cardiogenic (↓ CO, ↑ SVR), hypovolemic (↓ CO, ↑ SVR), obstructive (↓ CO), and mixed. Types of Shock)
  • Depression 
  • Pulmonary embolism Pulmonary Embolism Pulmonary embolism (PE) is a potentially fatal condition that occurs as a result of intraluminal obstruction of the main pulmonary artery or its branches. The causative factors include thrombi, air, amniotic fluid, and fat. In PE, gas exchange is impaired due to the decreased return of deoxygenated blood to the lungs. Pulmonary Embolism: due to prolonged immobility and deep vein thrombosis Deep vein thrombosis Deep vein thrombosis (DVT) usually occurs in the deep veins of the lower extremities. The affected veins include the femoral, popliteal, iliofemoral, and pelvic veins. Proximal DVT is more likely to cause a pulmonary embolism (PE) and is generally considered more serious. Deep Vein Thrombosis 
  • Pulmonary and urinary tract infections Urinary tract infections Urinary tract infections (UTIs) represent a wide spectrum of diseases, from self-limiting simple cystitis to severe pyelonephritis that can result in sepsis and death. Urinary tract infections are most commonly caused by Escherichia coli, but may also be caused by other bacteria and fungi. Urinary Tract Infections 

Prognosis

  • Recovery can occur up to 2 years after injury. 
  • Duration of recovery depends on the site and severity of the injury.  
  • Most individuals regain functional walking ability. 

Differential Diagnosis

  • Ischemic stroke Ischemic Stroke An ischemic stroke (also known as cerebrovascular accident) is an acute neurologic injury that occurs as a result of brain ischemia; this condition may be due to cerebral blood vessel occlusion by thrombosis or embolism, or rarely due to systemic hypoperfusion. Ischemic Stroke: also known as a cerebrovascular accident Cerebrovascular accident An ischemic stroke (also known as cerebrovascular accident) is an acute neurologic injury that occurs as a result of brain ischemia; this condition may be due to cerebral blood vessel occlusion by thrombosis or embolism, or rarely due to systemic hypoperfusion. Ischemic Stroke. Ischemic stroke Ischemic Stroke An ischemic stroke (also known as cerebrovascular accident) is an acute neurologic injury that occurs as a result of brain ischemia; this condition may be due to cerebral blood vessel occlusion by thrombosis or embolism, or rarely due to systemic hypoperfusion. Ischemic Stroke is an acute neurologic injury resulting from brain ischemia. The clinical presentation includes neurologic symptoms with varying degrees of motor and sensory loss corresponding to the area of the brain affected and the extent of the tissue damage. Diagnosis is made by physical examination and imaging. Management is ideally with thrombolytic therapy to restore blood flow if the time frame and clinical situation permit.
  • Syringomyelia: formation of a fluid-filled cyst within the spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord, called a syrinx, that can expand and elongate over time. Damage to the spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord may result in sensory and motor deficits related to the level affected. This often includes a cape-like bilateral loss of pain Pain Pain has accompanied humans since they first existed, first lamented as the curse of existence and later understood as an adaptive mechanism that ensures survival. Pain is the most common symptomatic complaint and the main reason why people seek medical care. Physiology of Pain and temperature sensation along the upper chest and arms. Diagnosis is made by MRI imaging and management is with surgical intervention in individuals with severe symptoms. 
  • Anterior cord syndrome Anterior cord syndrome Anterior cord syndrome (ACS) is an incomplete cord syndrome predominantly affecting the anterior (ventral) …” of the spinal cord while sparing the dorsal columns. Anterior cord syndrome can be caused by occlusion of the anterior spinal artery or by trauma, which results in disc herniation and bone fragments disrupting the spinal cord. Anterior Cord Syndrome (ACS): incomplete cord syndrome to the anterior (ventral) ⅔ of the spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord while sparing the dorsal columns. Anterior cord syndrome Anterior cord syndrome Anterior cord syndrome (ACS) is an incomplete cord syndrome predominantly affecting the anterior (ventral) …” of the spinal cord while sparing the dorsal columns. Anterior cord syndrome can be caused by occlusion of the anterior spinal artery or by trauma, which results in disc herniation and bone fragments disrupting the spinal cord. Anterior Cord Syndrome can be caused by occlusion of the anterior spinal artery or trauma causing disc herniation and bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Structure of Bones fragments that disrupt the spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord. Clinical manifestations are loss of motor and sensory function below the level of injury. Diagnosis of ACS is by clinical exam and neuroimaging with MRI. Management is directed at resolving the underlying cause.
  • Central cord syndrome Central Cord Syndrome Central cord syndrome (CCS) is a neurological syndrome caused by an injury to the center of the spinal cord, affecting the spinothalamic tracts ((STTs) sensory) and medial aspect of the corticospinal tracts ((CSTs) motor), most often due to trauma in patients with cervical spondylosis. Central Cord Syndrome (CCS): neurologic syndrome caused by injury to the center of the spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord, affecting the spinothalamic tracts (sensory) and medial aspect of the corticospinal tracts (motor). Clinical manifestations are motor deficits in the arms more than the legs and variable Variable Variables represent information about something that can change. The design of the measurement scales, or of the methods for obtaining information, will determine the data gathered and the characteristics of that data. As a result, a variable can be qualitative or quantitative, and may be further classified into subgroups. Types of Variables sensory deficits below the level of injury. Diagnosis is made clinically and is supported with neuroimaging. Definitive management can be medical or surgical depending on the severity of the injury.
  • Multiple sclerosis Multiple Sclerosis Multiple sclerosis (MS) is a chronic inflammatory autoimmune disease that leads to demyelination of the nerves in the CNS. Young women are more predominantly affected by this most common demyelinating condition. Multiple Sclerosis: autoimmune disorder wherein the immune system targets the myelin protective sheath covering the nerve fibers. Clinical presentation is with visual symptoms, tremors, unsteady gait, numb or weak limbs, slurred speech, fatigue, and dizziness. Diagnosis is made by clinical presentation, MRI imaging, and evoked-potential tests. Management is supportive and targeted toward attacks and slowing progression of the disease.  
  • Decompression sickness (DCS): known informally as “the bends.” Decompression sickness is caused by compression and decompression of gases contained in the body during descent and rapid ascent while diving. Clinical presentation of DCS may be nonspecific and variable Variable Variables represent information about something that can change. The design of the measurement scales, or of the methods for obtaining information, will determine the data gathered and the characteristics of that data. As a result, a variable can be qualitative or quantitative, and may be further classified into subgroups. Types of Variables, with time of onset varying from immediately after surfacing to 12 hours later. Diagnosis is made clinically. Management is early supportive therapy and hyperbaric recompression treatment.

References

  1. Shams, S., Arain, A. (2021). Brown Séquard syndrome. StatPearls. Retrieved September 29, 2021, from https://www.ncbi.nlm.nih.gov/books/NBK538135/.
  2. Halvorsen, A., Pettersen, A.L., Nilsen, S.M., Halle, K.K., Schaanning, E.E., Rekand, T. (2019). Epidemiology of traumatic spinal cord injury in Norway in 2012-2016: a registry-based cross-sectional study. Spinal Cord 57:331–338. https://www.nature.com/articles/s41393-018-0225-5.
  3. Hachem, L.D., Ahuja, C.S., Fehlings, M.G. (2017). Assessment and management of acute spinal cord injury: from point of injury to rehabilitation. Journal of Spinal Cord Medicine 40:665–675. https://doi.org/10.1080/10790268.2017.1329076.
  4. Decker, J.E., Hergenroeder, A.C. (2020). Overview of cervical spinal cord and cervical peripheral nerve injuries in the child or adolescent athlete. UpToDate. Retrieved September 30, 2021, from https://www.uptodate.com/contents/overview-of-cervical-spinal-cord-and-cervical-peripheral-nerve-injuries-in-the-child-or-adolescent-athlete.

USMLE™ is a joint program of the Federation of State Medical Boards (FSMB®) and National Board of Medical Examiners (NBME®). MCAT is a registered trademark of the Association of American Medical Colleges (AAMC). NCLEX®, NCLEX-RN®, and NCLEX-PN® are registered trademarks of the National Council of State Boards of Nursing, Inc (NCSBN®). None of the trademark holders are endorsed by nor affiliated with Lecturio.

Study on the Go

Lecturio Medical complements your studies with evidence-based learning strategies, video lectures, quiz questions, and more – all combined in one easy-to-use resource.

Learn even more with Lecturio:

Complement your med school studies with Lecturio’s all-in-one study companion, delivered with evidence-based learning strategies.

User Reviews

0.0

()

¡Hola!

Esta página está disponible en Español.

🍪 Lecturio is using cookies to improve your user experience. By continuing use of our service you agree upon our Data Privacy Statement.

Details