Woo hoo! It's time for recess! You run out to the playground as quickly as possible, so that you can be first in line for the swings. Your best friend comes along and offers to push you. You swing higher and higher, waiting for the right moment to launch yourself forward into a perfect landing on the soft grass.
As your friend gives you one last push, you arch your back and wait for the swing to reach the peak of its arc. At the last possible moment, you let go of the chains and leap forward through the air. As your feet hit the ground, though, you stumble forward and bang your knee against the ground. Oh well, it wasn't a perfect landing, but it was fun!
Your knee isn't bleeding, so you get up and continue playing. Throughout the rest of the school day, you notice your knee is a little tender, but it appears fine. You head home at the end of the day and complete your homework. When it's time for dinner, you head to the table and bump your knee as you sit down.
Ouch! That little bump with the kitchen table hurt more than it usually does. You pull your leg out from beneath the table to examine it more closely. You're surprised to see an area on your knee that's starting to turn dark. What's going on here? Looks like that fall on the playground bruised your knee!
But what exactly is a bruise? A doctor would call that bruise a contusion. Bruises form when the soft tissues of your body get injured but your skin doesn't break. Even a small bump can injure the soft tissues of your skin.
The tiny blood vessels in your skin can break when your skin is impacted, like when you bump into something or a ball hits you. When these tiny blood vessels break, red blood cells leak out and collect under your skin. Depending upon where they collect and how many red blood cells there are, your bruise may appear black. blue, red, or purple.
Each person is unique. Some people bruise very easily. Others may have tougher skin tissue that will not bruise as easily. For some people, bumping into a door in the middle of the night may lead to a bruise on the arm, while others may play an entire tackle football game without a single bruise.
Bruises go through phases as the body heals itself. At first, the bruise will be tender to the touch and may even swell as blood collects under the skin. It will also change colors. What starts out as red or purple will turn to blue and even black after a couple of days.
Over time, the body metabolizes or breaks down the blood cells under the skin. As it does so, the color of your bruise may change to green or even yellow. After a week or so, your bruise will likely change to a light brown color that will continue to fade to lighter and lighter shades as it disappears over the course of another week or so.
Most bruises go away on their own over the course of a couple of weeks, if not sooner. If a bruise gets worse or lasts longer than two weeks, be sure to let an adult friend or family member know. Bruises lasting longer than two weeks can be a sign of a more serious problem, and you may need to see a doctor.
There's not much you can or need to do for a bruise. Using a cold compress can reduce swelling, if that's an issue. However, preventing bruises by wearing appropriate clothing and safety gear is the best way to avoid them altogether!