You might just think of your spine as the stack of bones that keeps you upright or hurts when you slump, but that doesn't even scratch the surface of everything that the spinal column does for the human body.
What is the spinal cord? Every move you make — from blinking your eyes to stretching your toes — happens thanks to the spine's bundle of nerves, which transmits messages from your brain to the rest of your body.
But there's so much more your spine can do that you've probably never even considered. First, though, let's simplify things.
What Is the Spinal Cord?
As the mastermind of body movements, the spinal cord is a long channel of nerves that — alongside the brain — creates the central nervous system. Those nerves are surrounded and protected by both the vertebrae (bones) and the spinal discs (tissues) that run down the backbone.
In a way, it's kind of like a communication superhighway for the body. Whether you need to type an email or walk the dog, the brain sends the order, which travels through the spinal cord until it reaches the right destination. Then, movement happens.
7 Mind-Blowing Spinal Facts
You might have already known about the spinal cord's role in the nervous system — but what you might not know is that the spine and spinal cord work in fascinating ways. From learning how the spinal cord heals to what part of the spine controls the bladder, read on for a few facts that might just blow your mind.
1. It Works Without You Knowing
Sometimes, the spinal cord follows commands without you even knowing about them. This encompasses all your body's involuntary movements, like your eyes dilating with light, or your digestive system working to process your lunch.
2. It Hasn't Grown Since You Were 4 Years Old
The spinal cord matures physically when we reach four years old. At that point, it's as long as it's ever going to get. The vertebrae and spinal discs, on the other hand, continue growing.
3. It's About as Thick as Your Fingernail
The spinal cord might have the storage capacity of a superhighway, but it's nowhere near the size of one. At just 1–1.5 centimeters thick, it's actually quite small.
4. It Sends Healing Reflexes
When you hurt yourself — whether you burn your hand on the stove or scrape your knee from a fall — pain messages travel via the spinal cord from the source of the injury to your brain. From there, the brain might send back a message through the spinal cord to deploy white blood cells to help you recover.
5. It Controls Your Bowels and Bladder
Five parts make up the spinal column. From top to bottom, they're the cervical (closest to the skull), thoracic, lumbar, sacral and coccygeal (the tailbone). Each has different responsibilities and controls different parts of the body. If you're wondering what part of the spine controls the bladder, it's the same part that controls the bowels: the sacral.
6. It Creates Shortcuts for Regular Activities
There are so many things that you do so often, they're practically on auto-pilot — from taking steps to turning the steering wheel. The reason these movements come so easily is because your spinal cord has stored them as shortcuts in the nervous system, which means it takes less time for the information to trigger the right movements.
7. It Can Grow Taller in Space
If you plan on taking a trip to Mars anytime soon, you might want to pack new pants. That's because the effects of gravity can space out the vertebrae, making astronauts taller — but only temporarily so. When you come back to Earth, the greater gravity will condense the spaces back to their original height.
Why Protecting Your Spine Health Matters
To protect yourself, wear a seat belt when driving, be safe when playing sports and work to prevent against falls — as these factors contribute to the most common reasons for spinal cord injuries.