Table of ContentsView AllTable of ContentsFunctionAnatomyRegionsGray and White MatterConditionsTreatment
Table of ContentsView All
View All
Table of Contents
Function
Anatomy
Regions
Gray and White Matter
Conditions
Treatment
The main function of the spinal cord is to carry nerve signals between your brain and the rest of your body. This includes motor commands and sensory information. The spinal cord also helps coordinate your reflexes.
The spinal cord is part of the central nervous system. It runs down the center of your back and is primarily composed of nerves, which are organized in systematic pathways, also described as tracts. The spine (backbone) encloses and protects the spinal cord.
ericsphotography/E+/Getty Images
What Is the Function of the Spinal Cord?
The primary role of the spinal cord in the nervous system is to relay sensory, motor, and autonomic messages between the brain and the rest of the body.Myelinated nerves along the pathways of the spinal cord send electrical signals to each other to facilitate these actions.
Anatomy and Location
The spinal cord is adjacent to and below themedulla, which is the lowest part of the brain. The top region of the spinal cord extends down from the medulla all the way to the lower back.
Spinal Cord vs. Vertebral ColumnThe spinal cord is a band of nerves and cells, while the vertebral column is the term used to describe the bones of your spine, which cover and protect the spinal cord.
Spinal Cord vs. Vertebral Column
The spinal cord is a band of nerves and cells, while the vertebral column is the term used to describe the bones of your spine, which cover and protect the spinal cord.
What Are the Regions of the Spinal Cord?
From top to bottom, the regions of the spinal cord include
Each of these levels corresponds to spinal nerves that emerge from the spinal cord toward structures of the body, such as the arms, legs, and trunk.
How long is the spinal cord?In most adults, the spinal cord is about 18 inches long.
How long is the spinal cord?
In most adults, the spinal cord is about 18 inches long.
Gray Matter and White Matter
The deep, central area of the spinal cord is referred to as gray matter, and the portion that is located nearer to the outer edge of the spinal cord is referred to as white matter.
A coating calledmyelin(a type of fat) insulates all nerves. The white matter tends to have more myelination than the grey matter, giving it a whiter appearance when viewed with a microscope.
The grey matter of the spinal cord is shaped somewhat like an open-winged butterfly lying across the center of the spinal cord. This butterfly-shaped gray matter contains nerve roots. The white matter is composed of several tracts (pathways) that travel up and down the spinal cord.
Sections of the spinal cord include the following.
Anterior Horn
This section is the frontal portion of the gray matter of the spinal cord, and it is composed of nerves that send motor signals to the spinal nerves.
Lateral and Anterior Tracts
These white matter pathways carry motor signals down the spinal cord in the corticospinal tract. This tract travels all the way down the spinal cord at the front and sides of the white matter regions.
Motor control of the voluntary muscles (muscles you choose to move) travels through the spinal cord in the corticospinal tract. Motor signals are initiated in the motor strip, a region of the cerebral cortex of the brain.
Dorsal Horn
These motor signals travel down the internal capsule, and then cross over to the other side of the body in the brain stem. From there, these messages are sent to the anterior horn and the lateral and anterior tracts of the spinal cord. The motor message exits the spinal cord through the ventral root (the front portion) of the spinal nerves.
This area is the posterior region of the grey matter. The spinal nerves deliver sensory messages such as light touch, position sense, and vibration to the dorsal horns.
Posterior Tracts
Also described as the spinothalamic tract, this is a long, white matter pathway that extends all the way up the spine to the brain. The spinal cord mediates sensation coming from the skin, bones, and internal organs.
Your skin detects these sensations and sends messages from peripheral sensory nerves (embedded in the skin) to the spinal nerves, then to the dorsal horn and up through the spinothalamic tracts, crossing over to the other side of the spinal cord before reaching the brain.
Eventually, these messages reach the brain stem, then the thalamus, and then the sensory strip, which is directly behind the motor strip in the cerebral cortex of the brain.
Lateral Horn
The lateral horns of the spinal cord are located at the two sides of the gray matter. This area is composed of nerves that mediate autonomic functions of the body. The autonomic nervous system regulates involuntary functions (actions you don’t purposely control), such as digestion and breathing.
Associated Conditions
There are a number of medical problems that can affect the spinal cord. Disease of the spinal cord is often described asmyelopathy. These conditions cause impairment of motor, sensory, and/or autonomic function.
Diagnosis of a spinal cord condition can include tests such as a physical examination, spinal imaging, nerve conduction studies (NCV), and/or electromyography (EMG).
Conditions that affect the spine include:
Multiple Sclerosis (MS)
This is ademyelinatingcondition that may affect the brain and/or spine.Multiple sclerosislesions in the spine can cause weakness, sensory loss, tingling, and pain, and they may affect bowel and bladder function.
Spinal Cord Compression
When thespinal cord is placed under physical pressure, weakness, sensory loss, and autonomic deficits can occur. Severe degenerative disease of the bone or cartilage of the spine can cause these structures to fall out of place—potentially resulting in physical impingement on the spinal cord. Metastatic (spreading throughout the body) cancer can cause spinal cord compression as well.
Trauma
An injury can cause the spine to move out of place and can even cause a spine fracture (break), which caninjure the spinal cord. Injuries may also cause spinal cord compression due to bleeding, and an injury can directly damage the spinal cord.
What happens if the spinal cord is damaged?An injury to the spinal cord can cause a range of symptoms, depending on where the injury occurred. Injuries that happen higher up on the spinal cord tend to be more severe. When the spinal cord is injured at the neck, it may cause problems with breathing. An injury to the spinal cord in the lower back may cause problems with bladder and bowel control. Some injuries can cause partial or complete paralysis.
What happens if the spinal cord is damaged?
An injury to the spinal cord can cause a range of symptoms, depending on where the injury occurred. Injuries that happen higher up on the spinal cord tend to be more severe. When the spinal cord is injured at the neck, it may cause problems with breathing. An injury to the spinal cord in the lower back may cause problems with bladder and bowel control. Some injuries can cause partial or complete paralysis.
Amyotrophic Lateral Sclerosis (ALS)
Currently, there is no cure for ALS. However, medications can help relieve the symptoms and improve quality of life, such as:
Meningitis
An infection or inflammation of the meninges, often described as spinal meningitis, can cause symptoms such as a headache, stiff neck, fever, nausea, and vomiting.Episodes of bacterial meningitis require antibiotics. Other types of meningitis may require anti-inflammatory therapy or other treatments that target the cause.
Vitamin B12 Deficiency
A deficit in this vitamin can cause manymedical issues, including anemia, nerve damage, and subacute combined degeneration of the spinal cord, which is a very rare demyelinating condition that can cause weakness, sensory loss, and stiffness.
Cancer
Spinal cord cancer is not common, but tumors can develop in any region of the spinal cord. Late-stage cancer often metastasizes to the spine and/or spinal cord, causing spinal cord compression.Meningeal carcinomatosis is the spread of cancer cells throughout the meninges and CSF.
Spinal Cord Infarct
If the blood supply to the spinal cord is interrupted, an area of the spine might not receive an adequate supply of blood. This can lead to severe damage, with resulting loss of spinal cord function.
Spinal Muscular Atrophy (SMA)
Polio
Spinal cord diseases and injuries typically require medical and/or surgical interventions. Treatment may include steroids to reduce inflammation or antibiotics to target bacterial infections. Certain neurological conditions, such as MS, ALS, and SMA, also can improve with prescription medications indicated for the specific conditions.
If you have spinal cord compression, you may need surgery to reduce pressure on your spinal cord due to cancer or a bone impingement. Cancer may require treatment with chemotherapy and radiation therapy.
Therapies also usually include physical therapy and rehabilitation exercises. Some people may need to use a cane, walker, or wheelchair while recovering from a condition involving the spinal cord.
Summary
9 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Cho TA.Spinal cord functional anatomy.Continuum (Minneap Minn). 2015;21(1 Spinal Cord Disorders):13-35. doi:10.1212/01.CON.0000461082.25876.4aAmerican Association of Neurological Surgeons.Anatomy of the spine and peripheral nervous system.National Institute of Neurological Disorders and Stroke.Transverse myelitis.Ziu E, Mesfin FB.Spinal metastasis. StatPearls.Johns Hopkins Medicine.Acute spinal cord injury.ALS Association.Medications for treating ALS.National Institute of Neurological Disorders and Stroke.Meningitis.MedlinePlus.Vitamin B12.Menant JC, Gandevia SC.Poliomyelitis.Handb Clin Neurol. 2018;159:337-344. doi:10.1016/B978-0-444-63916-5.00021-5
9 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Cho TA.Spinal cord functional anatomy.Continuum (Minneap Minn). 2015;21(1 Spinal Cord Disorders):13-35. doi:10.1212/01.CON.0000461082.25876.4aAmerican Association of Neurological Surgeons.Anatomy of the spine and peripheral nervous system.National Institute of Neurological Disorders and Stroke.Transverse myelitis.Ziu E, Mesfin FB.Spinal metastasis. StatPearls.Johns Hopkins Medicine.Acute spinal cord injury.ALS Association.Medications for treating ALS.National Institute of Neurological Disorders and Stroke.Meningitis.MedlinePlus.Vitamin B12.Menant JC, Gandevia SC.Poliomyelitis.Handb Clin Neurol. 2018;159:337-344. doi:10.1016/B978-0-444-63916-5.00021-5
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Cho TA.Spinal cord functional anatomy.Continuum (Minneap Minn). 2015;21(1 Spinal Cord Disorders):13-35. doi:10.1212/01.CON.0000461082.25876.4aAmerican Association of Neurological Surgeons.Anatomy of the spine and peripheral nervous system.National Institute of Neurological Disorders and Stroke.Transverse myelitis.Ziu E, Mesfin FB.Spinal metastasis. StatPearls.Johns Hopkins Medicine.Acute spinal cord injury.ALS Association.Medications for treating ALS.National Institute of Neurological Disorders and Stroke.Meningitis.MedlinePlus.Vitamin B12.Menant JC, Gandevia SC.Poliomyelitis.Handb Clin Neurol. 2018;159:337-344. doi:10.1016/B978-0-444-63916-5.00021-5
Cho TA.Spinal cord functional anatomy.Continuum (Minneap Minn). 2015;21(1 Spinal Cord Disorders):13-35. doi:10.1212/01.CON.0000461082.25876.4a
American Association of Neurological Surgeons.Anatomy of the spine and peripheral nervous system.
National Institute of Neurological Disorders and Stroke.Transverse myelitis.
Ziu E, Mesfin FB.Spinal metastasis. StatPearls.
Johns Hopkins Medicine.Acute spinal cord injury.
ALS Association.Medications for treating ALS.
National Institute of Neurological Disorders and Stroke.Meningitis.
MedlinePlus.Vitamin B12.
Menant JC, Gandevia SC.Poliomyelitis.Handb Clin Neurol. 2018;159:337-344. doi:10.1016/B978-0-444-63916-5.00021-5
Meet Our Medical Expert Board
Share Feedback
Was this page helpful?Thanks for your feedback!What is your feedback?OtherHelpfulReport an ErrorSubmit
Was this page helpful?
Thanks for your feedback!
What is your feedback?OtherHelpfulReport an ErrorSubmit
What is your feedback?
