Written by John Kyle D. Buenavista

Edited and Reviewed by Reuben J C. Los Baños, Ph.D.

The spinal cord is a key part of the central nervous system. It serves as the main link between the brain and the body. It sends signals that control movement, sensation, and reflexes. It makes it essential for how the body works. This article discusses the structure and function of the spinal cord. It also covers common disorders that affect it and ways to keep your spine healthy.

Structure of the Spinal Cord

It begins at the brainstem in the region known as the medulla oblongata. It runs down the spine to about the first or second lumbar vertebra (L1–L2) in adults. There, it narrows into the conus medullaris. Below this point, a bundle of nerves called the cauda equina goes down the lower vertebral canal. It allows for safe lumbar punctures.

The vertebral column protects the spinal cord. It is a bony structure with 33 vertebrae. Doctors divide these vertebrae into different regions:

• Cervical (Neck) – 7 vertebrae (CC1–C7)
• Thoracic (Upper Back) – 12 vertebrae (T1–T12)
• Lumbar (Lower Back) – 5 vertebrae (L1–L5)
• Sacral (Pelvis) – 5 fused vertebrae (S1–S5)
• Coccygeal (Tailbone) – 4 fused vertebrae (Co1)

The subarachnoid space sits between the arachnoid and the pia mater. It holds the cerebrospinal fluid (CSF), cushions the spinal cord, and helps remove Waste.

Function of the Spinal Cord

The spinal cord is a key communication highway. It carries signals from the brain to the body. Its primary functions include:

• Movement Control – Transmitting motor commands from the brain to muscles, allowing voluntary movement.
• Sensory Processing tells your brain when you feel touch, pain, or heat.
• Reflex Coordination – It controls quick, automatic actions. One example is the knee-jerk reaction.
• Autonomic Regulation – controls functions like heart rate, blood pressure, and digestion. It works through the autonomic nervous system.

Disorders of the Spinal Cord

Injuries or disorders can affect us. The spinal cord is essential for almost all body functions. Some common spinal cord disorders include:

• Spinal Cord Injury (SCI) is damage to the spinal cord. It can lead to partial or total loss of sensation and motor control.
  • Herniated Disks—The soft disks between your spine’s bones can bulge or tear. It can cause pain and pressure on the spinal cord or nerves.
  • Spinal Stenosis happens when the spinal canal narrows. It can squeeze the spinal cord, leading to pain or nerve problems.
  • Transverse Myelitis is when the spinal cord gets inflamed. It can cause paralysis and loss of sensation.

Maintaining Spinal Cord Health

To keep your spinal cord healthy and lower the chance of injury or disease, try these tips:

• Stay active, strengthen your core, and maintain good posture.
• Eat a Balanced Diet – Good nutrition helps keep your bones strong and your nerves working well.
• Practice Good Posture – Avoid prolonged slouching or awkward positions that strain the spine.
• Bend your knees to ensure a safe lift.
• Keep your back straight when picking up heavy things.
• Avoid Smoking and Drinking Too Much – These habits can harm bones and affect how nerves work.

What type of tissue do we find in the spinal cord?

The spinal cord is part of the central nervous system and is a crucial link between the brain and the body. It consists of nervous tissue, one of the four basic tissue types in the human body. The other types are epithelial, muscle, and connective tissues. Nervous tissue conducts electrical impulses and integrates sensory and motor information. This tissue supports key body functions like movement, reflexes, and organ control.

Nervous Tissue: The Core of the Spinal Cord

The spinal cord has two main parts: neurons and neuroglial cells.

• Neurons are the functional units of the nervous system. They are special cells that create and send electrical signals called nerve impulses. Spinal cord neurons send sensory information from the body to the brain. It sends motor commands from the brain to muscles and organs.
• Neuroglial cells (glial cells) provide neurons with support, protection, and nourishment. Types of glial cells in the spinal cord include astrocytes, oligodendrocytes, and microglia.

Researchers group spinal cord neurons by their functions. Neuroglial cells surround these neurons, keeping them healthy and protected. Without neuroglial cells, neurons would not function.

Gray Matter and White Matter

The spinal cord has two central regions of nervous tissue. Each one has its unique function:

• Gray Matter: Gray matter is in the center of the spinal cord. It looks like a butterfly when you look at it in cross-section. It consists of neuronal cell bodies, dendrites, and unmyelinated axons. This region handles synaptic integration. It processes information and coordinates reflexes. The Gray matter is essential for local communication within the spinal cord.
• White Matter: The white matter surrounds the gray matter. It has myelinated axons. Myelin is a fatty material made by oligodendrocytes. It wraps around axons and helps nerve impulses travel faster. White matter has two main types of tracts. Ascending tracts carry sensory information to the brain. Descending tracts send motor commands from the brain to the body. The presence of myelin gives this area its white appearance.

As the Cleveland Clinic describes, these tissues transmit messages between the brain and the rest of the body, allowing for voluntary movement, reflex actions, and involuntary autonomic functions like heart rate and respiration (Cleveland Clinic, n.d.).

More Supporting Tissues

Nervous tissue is the primary type in the spinal cord, but other tissues also help it work:

• Connective Tissue: The spinal cord has three layers of connective tissue. These layers are the meninges.
  • The three layers are:
    • Dura mater (outer layer)Arachnoid mater (middle layer)Pia mater (innermost layer)
    These layers help protect the nervous tissue and anchor the spinal cord.

• Epithelial Tissue: Ependymal cells are a kind of epithelial tissue. They run along the central canal of the spinal cord. They help create and transport cerebrospinal fluid (CSF). This fluid cushions and nourishes the spinal cord.

Clinical Relevance

Understanding the type of tissue in the spinal cord has important medical implications. Several problems can damage nervous tissue.

These include multiple sclerosis, spinal cord injuries, tumors, and infections. Damage to white matter blocks signals between the brain and body. In contrast, damage to gray matter affects reflexes and coordination.

Doctors perform lumbar punctures with great precision. They insert the needle below the L2 vertebral level. It helps prevent harm and lowers the risk to central nervous tissue.

What is the tissue between the spine?

The intervertebral disc is the tissue between the vertebrae in the spine. Fibrocartilaginous tissue makes these discs. They act like shock absorbers for the spine.

Structure of the Intervertebral Disc

Two main parts compose each intervertebral disc:

Annulus Fibrosus

• It is the tough outer layer of the disc made up of fibrous connective tissue.
  • It has several rings (lamellae) made of collagen fibers. These rings give strength and prevent excessive movement between vertebrae.
  • Its primary role is to contain and protect the softer inner part of the disc.
• Nucleus Pulposus
  • Located in the center of the disc, this is a gel-like substance with high water content.
  • It provides shock-absorbing features to the disc. It helps spread pressure when moving or bearing weight.
  • The nucleus pulposus can lose hydration as people age, making the disc less effective.

According to the University of Maryland Medical Center, this two-part structure allows the spine to handle compression and bending forces while maintaining its shape and flexibility (UMMC, n.d.).

Function of the Intervertebral Discs

• Shock Absorption: The discs absorb impacts during walking, lifting, and running.
• Spinal Flexibility: They enable bending and twisting movements of the spine.
• Discs create space between vertebrae. They prevent rubbing and let nerves exit the spinal canal without compression.

Clinical Relevance

Injury or wear to the intervertebral disc can lead to problems. These include herniated discs and degenerative disc disease. A herniated disc happens when the soft center of a spinal disc pushes out through a tear in the outer layer. It can press on spinal nerves, leading to pain, numbness, or weakness.

The intervertebral disc sits between the spine’s bones.

What are the soft tissues in the spinal cord?

The soft tissues in the spinal cord are:

• The spinal cord
• protective meninges
• intervertebral discs
• ligaments
• muscles
• tendons

These components protect the spinal cord, help movement, and maintain spinal stability. Breakdown of Soft Tissues:

• Spinal Cord: A column of nerves that transmits signals between the brain and the rest of the body.
• Meninges: Three protective layers surrounding the spinal cord:
• Dura mater: The tough outer layer.
• Arachnoid mater: The middle web-like layer.
• Pia mater: The delicate inner layer that fits around the spinal cord.
• Intervertebral Discs: Cushion-like pads between vertebrae that absorb shock and allow flexibility.
• Ligaments: Fibrous tissues connecting bones, providing stability to the spine.Muscles: Support the spine and ease movement.
• Tendons: Connect muscles to bones, aiding in movement and maintaining posture.

These soft tissues shield the spinal cord. They help with movement and support the body’s structure.

What are the three layers of connective tissue around the spinal cord?

The Three Layers of Connective Tissue Around the Spinal Cord

The brain and spinal cord comprise the central nervous system (CNS). Three layers of special connective tissue called the meninges protect them. These membranes support the structure, cushion the CNS, and block injury and infection.

The three meningeal layers, from outermost to innermost, are:

• Dura mater
• Arachnoid mater
• Pia mater

Dura Mater: The Tough Outer Layer

The dura mater is the outermost and most durable layer. It sits below the skull and spine. It has two layers: the outer periosteal layer connects to the bone. The inner meningeal layer is near the brain and spinal cord. This tough membrane serves as the primary protective shield for the CNS.

The dura mater also plays a vital role in venous drainage. It has channels called dural venous sinuses, which collect and drain blood from the brain. The dura mater also contains the middle meningeal artery, a key blood supply source. Plus, it offers a path for several cranial nerves, like the trigeminal nerve. Dural reflections are inward folds of the dura. They help anchor and compartmentalize the brain.

Arachnoid Mater: The Web-Like Middle Layer

The arachnoid mater sits below the dura mater. It is a thin, transparent membrane that looks like a spiderweb. Although avascular and lacking nerves, this layer is critical in cushioning the CNS. It spans the brain’s sulci and links to the pia mater below. Delicate strands called arachnoid trabeculae make this connection.

The subarachnoid space sits between the arachnoid and the pia mater. It has cerebrospinal fluid (CSF). CSF absorbs shocks, circulates nutrients, and removes Waste from the CNS.

Pia Mater: The Delicate Inner Layer

The pia mater is the innermost meningeal layer. It adheres to the brain and spinal cord, conforming to every fold and groove. The pia mater is delicate, but it has many blood vessels. These vessels go into the neural tissue to nourish the brain and spinal cord.

The pia mater supports the spinal cord’s structure. It also holds part of the CSF circulation system.

The Leptomeninges

We refer to the arachnoid and pia mater as the leptomeninges. It has a thin structure. This delicate layer works with the dura mater. Together, protect the CNS and support its function.

Meningeal Spaces and Their Functions

Three distinct spaces lie between or around the meningeal layers:

• Epidural Space: Space between the dura mater and the vertebral wall. It’s often used to give anesthesia during childbirth or surgery.
  • Subdural Space: This area sits between the dura and the arachnoid mater. It usually stays closed, but it can open up during trauma, like in a subdural hematoma.
  • Subarachnoid Space: This space is between the arachnoid and the pia mater. It holds CSF, which cushions and protects the CNS.

Functions of the Meninges

The meninges serve several vital roles:

• Protection: It shields the CNS from injury and stabilizes the skull’s brain.
  • Support: It houses and supports blood vessels, lymphatics, and nerves.
  • Storage: It nourishes, cushions, and cleans the brain and spinal cord.

Clinical relevance

Several medical conditions can affect the meninges:

• Meningitis: This is an infection that causes inflammation of the meninges. It usually shows symptoms like headache, fever, and neck stiffness.
• Meningiomas are usually benign tumors that originate from meningeal tissue. Yet, they can sometimes grow big enough to cause neurological symptoms.
• Subdural Hematoma: This is bleeding that occurs between the dura and arachnoid mater. It often happens after head trauma.
• CSF Leak: A tear in the dura mater allows CSF to escape. It can lead to severe headaches and other issues.
• Meningeal Carcinomatosis is a rare but serious condition. In this case, cancer spreads to the meninges from another primary site.

What is the purpose of cerebrospinal fluid?

Cerebrospinal fluid (CSF) is a clear, watery fluid that flows around the brain and spinal cord. It plays a key role in protecting and supporting the central nervous system (CNS).

Where CSF Comes From

A group of cells in the choroid plexus makes CSF in the brain’s ventricles. The body produces approximately 400–600 mL of CSF each day, but only around 150 mL exists in the body at the same time. CSF undergoes regular absorption and replacement.

Main Functions of CSF

Protects the Brain and Spinal Cord

CSF works like a cushion. It protects the brain and spinal cord from injury. It absorbs shocks from falls or sudden movements. It also supports the brain by making it “float,” which reduces pressure on the lower parts of the brain.

Keeps the Environment Stable

The brain requires a stable environment to function. CSF helps control the amount of salt, sugar, and other substances around brain cells. It also removes harmful waste products that build up as the brain works.

Delivers Nutrients

CSF supplies the brain and spinal cord with nutrients such as glucose (sugar) and vitamins. It also helps move chemical messengers, like hormones and signals, between brain parts.

Removes Waste

As brain cells do their job, they produce Waste. CSF helps remove Waste, including cells, toxins, and byproducts from neurotransmitters.

What’s in CSF?

Compared to blood, CSF has:

• More sodium and chloride
• Less potassium and calcium
• Very little protein
• Almost no red blood cells (and very few white blood cells— less than 5)

Why CSF Matters in Medicine

Doctors often collect CSF through a lumbar puncture or spinal tap. This test checks for diseases of the brain and spine.

Some essential conditions related to CSF include:

• Meningitis: An infection that causes swelling in the brain coverings. CSF can show signs of bacteria or viruses.
• Hydrocephalus: When CSF builds up too much in the brain, it causes pressure.
• CSF Leak: If CSF leaks out, it can cause nasty headaches.
• Subarachnoid Hemorrhage: This is bleeding into the CSF spaces. It often happens after a head injury or a burst blood vessel.

In Summary

Cerebrospinal fluid is vital for:

• Protecting the brain and spinal cord
• Nourishing brain tissues
• Removing waste products
• Helping doctors diagnose brain problems

Without CSF, the brain couldn’t work or stay safe from injury.

Is the spinal cord an organ or tissue?

The spinal cord is a key part of the central nervous system. It sends signals from the brain to the body and back.

We will examine the spinal cord, covering its structure, function, and common disorders. We will also discuss ways to keep your spine healthy.

Structure of the Spinal Cord

The spinal cord is a long, tube-like structure made of nervous tissue. It runs from the brainstem to the lower back and ends at the conus medullaris. Protective layers called meninges surround the brain.

These layers, from outermost to innermost, include:

1. Dura Mater – The rigid, outermost layer that shields the spinal cord from physical damage.
2. Arachnoid Mater – This middle layer looks like a web. It cushions and protects the spinal cord.
3. Pia Mater – This is the thin layer that hugs the spinal cord. It brings blood vessels to nourish the cord.

The vertebral column also protects the spinal cord. This bony structure has 33 vertebrae divided into three central regions:

• Cervical (Neck) – 7 vertebrae
• Thoracic (Upper Back) – 12 vertebrae
• Lumbar (Lower Back) – 5 vertebrae

Disorders of the Spinal Cord

Injuries or disorders can affect us. It is because the spinal cord is crucial for almost all body functions. Some common spinal cord disorders include:

• Spinal Cord Injury (SCI) happens when the spinal cord gets damaged. It can lead to a loss of feeling or control of movement; in some cases, the loss is partial, while in others, it is total.
• Herniated Disks happen when the disks that cushion the vertebrae bulge or break. They press on the spinal cord or nerves.
• Spinal Stenosis occurs when the spinal canal narrows. This can squeeze the spinal cord, causing pain or nerve issues.
• Transverse Myelitis occurs when the spinal cord becomes inflamed. It can lead to paralysis and loss of sensation.

Maintaining Spinal Cord Health

To keep the spinal cord healthy and reduce the risk of injury or disease, consider the following tips:

• Do exercises that build core muscles and improve posture.
  • Eat a Balanced Diet – Maintain proper nutrition to support bone health and nerve function.
  • Practice Good Posture – Don’t slouch or stay awkward for too long. It can strain your spine.
  • Use Proper Lifting Techniques – Bend your knees, not your back, when lifting heavy objects.
  • Avoid Smoking and Drinking Too Much – These habits can harm bones and affect how nerves work.

References

Cleveland Clinic. (n.d.). Spinal cord. Retrieved May 4, 2025, from https://my.clevelandclinic.org/health/body/21946-spinal-cord

Cleveland Clinic. (n.d.). Spine: Anatomy, function, parts, segments & disorders.

Gerson & Schwartz, P.A. (n.d.). Is the spinal cord an organ? Injury Attorneys. Retrieved May 10, 2025, from https://www.injuryattorneyfla.com/blog/is-the-spinal-cord-an-organ/

Mayo                  Clinic.                  (n.d.).                  Meninges.                  Retrieved              from https://www.mayoclinic.org/diseases-conditions/meningioma/multimedia/meninges/img-2 0008665

Professional, C. C. M. (2024, December 19). Spinal cord. Cleveland Clinic. Retrieved from https://my.clevelandclinic.org/health/body/21946-spinal-cord

Professional, C. C. M. (2025, January 24). Spine structure and function. Cleveland Clinic. Retrieved                                                                                                                       from

https://my.clevelandclinic.org/health/body/10040-spine-structure-and-function

Professional, C. C. M. (2025, March 19). Meninges. Cleveland Clinic. Retrieved from https://my.clevelandclinic.org/health/articles/22266-meninges

Telano LN, Baker S. (2023, July 4). Physiology, Cerebral Spinal Fluid. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from https://www.ncbi.nlm.nih.gov/books/NBK519007/

U.S. National Cancer Institute SEER Training. (n.d.). Nervous tissue. Retrieved May 4, 2025, from https://training.seer.cancer.gov/anatomy/cells_tissues_membranes/tissues/nervous.html

University of Maryland Medical Center. (n.d.). Anatomy and Function of the Spine. Retrieved May                       4,                                       2025,                                              from https://www.umms.org/ummc/health-services/orthopedics/services/spine/patient-guides/a natomy-function#:~:text=Intervertebral%20Disc,center%20called%20the%20nucleus%2 0pulposus