Your spinal cord is a cylinder-shaped tube of tissue that runs through the center of your spine, from your brainstem to your lower back. It’s made of nerves and cells that carry messages from your brain to the rest of your body. Your spinal cord is one of the main parts of your nervous system.
What does the spinal cord do?
Your spinal cord carries nerve signals from your brain to the rest of your body and back. The signals are electrical messages that help almost everything in your body work correctly, including:
- Controlling your body’s movements and functions: Signals from your brain to other body parts let you move when you want to. They also control involuntary (autonomic) functions like your heartbeat and breathing. Involuntary functions happen automatically without you thinking about them.
- Reporting senses to your brain: Nerve signals from all over your body help your brain process and feel all of your senses, including pressure and pain.
- Managing your reflexes: Reflexes are automatic physical responses. The patellar reflex makes your lower leg kick forward when a healthcare provider taps your shin just below your kneecap (patella). Your spinal cord controls some reflexes without involving your brain.
Your spinal cord is like a much more important version of the cable that sends and receives your TV signal. Instead of transferring data back and forth about your favorite shows and movies, your spinal cord carries all the messages that help your body function and stay connected to your brain.
Anatomy
Where is the spinal cord located?
Your spinal cord starts at the bottom of your brainstem and runs the length of your spine. It ends in your lower back in a cone shape called the conus medullaris.
What are the three main parts of the spinal cord?
Your spinal cord has three areas that match the three sections of your spine:
- Cervical (your neck).
- Thoracic (your upper back).
- Lumbar (your lower back).
Which nerves are in the spinal cord?
There are 31 nerves connected to your spinal cord. Thirty of your spinal nerves are pairs (one on each side of your spinal cord), including:
- Eight cervical nerve pairs starting in your neck and running mostly to your face and head.
- Twelve thoracic nerve pairs in your upper body that extend to your chest, upper back and abdomen.
- Five lumbar nerve pairs in your lower back that run to your legs and feet.
- Five sacral nerve pairs in your lower back near your sacrum (the bottom part of your spine) that extend into your pelvis.
The final nerve is a bundle at the base of your spine called the cauda equina that gives sensation to your lower body.
What are the other structures of the spinal cord?
Your spinal cord is covered in layers of tissue called meninges (just like the ones that surround your brain). These protective tissues include:
- Dura mater: The outer layer that protects your spinal cord from injury.
- Arachnoid mater: The middle layer.
- Pia mater: The deepest inner layer.
What are the epidural and arachnoid spaces?
The epidural space is between the dura mater and arachnoid mater. It’s where healthcare providers insert epidurals during labor and childbirth.
The subarachnoid space is between the arachnoid mater and the pia mater. Here, cerebrospinal fluid (CSF) provides extra cushioning and protection for your spinal cord. If you need a lumbar puncture (spinal tap), a healthcare provider will insert a needle into the subarachnoid space, remove a sample of your CSF and test it for signs of infection.
Conditions and Disorders
Which conditions and injuries can affect the spinal cord?
Many health conditions and injuries can affect your spinal cord. Because your spinal cord is so important to your whole body’s ability to function, spinal cord injuries and disorders are serious. For some disorders, getting treatment quickly can lower your risk of long-term or permanent complications.
Any injury to your spinal cord can cause severe symptoms in the parts of your body below where the injury happens. Spinal cord damage can cause a loss of bladder control or paralysis.
Common conditions that can affect your spinal cord include:
- Acute transverse myelitis.
- Cervical spondylosis.
- Herniated disks.
- Spinal fractures.
- Spinal muscular atrophy.
- Spinal stenosis.
- Spinal tumors.
- Spinal infections (infections that start in your spine or spread there from somewhere else in your body).
Care
How can I keep my spinal cord healthy?
You can keep your spinal cord (and entire back) healthy by following these general tips:
- Follow a nutritious eating plan.
- Stay physically active and stretch often.
- Adjust your posture often throughout your day.
- Sleep in positions that support the natural curve of your neck and lower back.
- Quit smoking and avoid other tobacco products.
- Limit how much alcohol you drink and avoid recreational drugs.