Thursday, February 5, 2009

Apple #368: Bruises

When I don't get enough sleep, I tend to run into things. Corner of the desk, coffee table, edge of the chair, etc. In the past few days, I've bonked my left knee so many times, it looks like some inmate's watercolor experiment.

So I am curious, when I get a bruise, what's going on in there? I know that's old blood, but why is it just sitting in that one place and not whooshing away through the blood vessels? What are the color changes about? Is it possible to make a bruise go away faster, or do you just have to wait it out?

So many questions. . . .

Bruises on the knee of a woman named Jan who fell and hit the curb. The bruising was actually made worse by the fact that she had taken lots of aspirin not long before the injury.
(Photo from Bob & Jan Green's travel blog)

  • Bruises happen when something rams into you hard enough to cause capillaries or blood vessels to break, but your skin remains intact.
  • What we see as a bruise is actually the pooling of blood in one location under the skin.
  • The blood pools in this one spot because of clotting. When you get a cut and the blood eventually stops flowing and forms a scab, that's because the blood is able to clot faster than the blood flows. Same thing happens with a bruise. The blood vessels break, blood flows out, but then it begins to clot. What you see is the clotted blood, almost like a scab, under your skin.
  • People use the words "bruise," "contusion," and "hematoma" pretty interchangeably. I think we're dealing in shades of meaning, but I'm going to try to determine the difference.
  1. Contusion -- the thing that happened to cause the skin discoloration. The bonking and the visible signs that it has happened.
  2. Bruise -- layperson's term for the visible discoloration.
  3. Hematoma -- the pooling of blood under the skin. Sometimes a lot of blood can clot together and form almost a jelly-like mass. These types of hematomas can be quite severe and can take a several weeks to heal.

Kinds of Bruises

  • It is possible to get whacked in one spot and for the blood to trickle into another spot and pool up there.
  • One of these kinds of migrating bruises is called a "tramline" bruise. Say you get hit with a rod-shaped object, like a pipe. You would think that the bruise would show up exactly along that column where the pipe hit you, right? Not so. Actually, when the pipe pushes into the tissue, it forces the blood away from the impact, out to either side of where the pipe hit you. So you wind up with two parallel lines of bruises, or what looks like tram or train tracks.
  • A similar thing could happen if you get hit with something like a baseball. The bruise might show up in a circle around the spot where the ball actually hit you.

Bruise from a paintball. You can get an idea of the exact size and shape of the paintball from the darker discoloration around the spot where the ball struck him.
(Photo by Kev, from his Paintballin blog)

  • Any connective tissue can be bruised. This includes tendons, bones, and internal organs, as well as muscles.
  • Bone bruises can occur when two bones get rammed against each other, like as a result of a car accident, or when some object bangs into you where you don't have a lot of fat or muscle, and the bone takes the brunt of the impact.
  • In these cases, the impact is forceful enough to affect the tissue inside the bone and cause bleeding to occur in there. You probably won't see evidence of a bone bruise, since the bleeding has occurred inside the bone, not near the surface of the skin.

Color changes
  • If you've ever gotten a bruise, you know that as it heals and fades, it changes color. It might start out a livid purple or dark blue, and over time it will fade to greenish-blue, then to yellow, and disappear altogether.

Bruise from a dog bite, 10 minutes after the incident. Lots of swelling, color isn't really showing up much yet.

Same bruise, 5 hours later. Purple around the edges where the blood has collected the most, bright red at the center.

4 days later. It's begun to turn yellow at the center, where there was less blood collected to begin with. The outer edges will take the longest to fade.
(All 3 photos by Colleen AF Venable on Flickr)

  • What we think of as bruise "healing" is actually the slow removal of dried and decayed blood. White blood cells that show up in the area break apart those bits of old blood and carry them off. As they carry some bits away, other bits are left, and those different bits are what cause the changes in color.
  • What's interesting to me about this is that there's an order to this bruise healing business.
  • The purple, dark color is the hemoglobin. When the bruise first appears, that dark color is hemoglobin all over the place. Well, actually the dark color is the oxygen in the hemoglobin. Hemoglobin is a protein in your blood whose primary function is to carry oxygen around. Oxygen when it's contained under the skin appears blue.
  • After the white blood cells break down the hemoglobin, the next thing you can see is called biliverdin. This stuff is green (think of verdant pastures). This is actually a waste product that's left over after the hemoglobin in blood is broken down.
  • The biliverdin then gets broken down further and becomes bilirubin. This is yellow or sometimes yellowish brown.
  • Bilirubin is also a waste product. Normally, bilirubin gets carried to your liver and is excreted out in urine.
  • By the way, in some cases, a person might have more bilirubin than the liver can get rid of, and that's when you get jaundice. This is why people with diseased livers -- alcoholics -- tend to get lots of bruises that don't go away, and why people in advanced stages of alcoholism also get jaundiced. Too much bilirubin and the liver can't keep up.

The progression of color changes in a bruise as different chemical components in blood become more prevalent.
(Diagram from Dr. Bunn)

  • Researchers have tried to correlate the colors with ages of the bruise (some say, for example, that green or yellow equals about 18 hours old; others say yellow equals 4 days). But there are so many factors involved -- the rate at which an individual's blood circulates, blood pressure, temperature, even the time of day -- that it's very difficult to calculate a time of injury based on the color of a bruise.
  • All these colors can be more or less intense depending on the location of the blood vessels and the number of them that have been ruptured. The more blood vessels burst, the more blood that accumulates and the more vibrant the colors. Also, if the blood vessels are closer to the skin, the more pyrotechnic the bruise will appear to be.
  • This means that if you suffer a really severe impact at the deep tissue level, the bruise won't appear for several days. You might feel a lot of pain, but it is sometimes difficult for medical professionals to identify what it is because there is no visible sign of bruising right away.

Speeding Recovery

  • There isn't a whole lot you can do to make a bruise go away, except the old maxim, RICE:
  1. Rest
  2. Ice
  3. Compression
  4. Elevation.
  • Applying ice within the first 24 hours can sometimes help. This numbs the pain, and it also can reduce the swelling and slow bleeding.
  • If you do apply ice, make sure you're not putting ice directly on your skin (you can get frostbite). Instead, wrap the ice in a towel, or better yet, use a bag of frozen peas. The peas hold the cold but they are small enough that they can cluster around the shape of your arm or leg or whatever.

This guy is using a bag of frozen peas to ice his aching shoulder. But you could do something similar for a bruise.
(Photo by mare, from his blog called loglog)

  • Apply ice only for about 10 to 15 minutes.
  • Following ice, it may help to wrap a bandage around the area. If it's especially tender, you may not want to include this step. Be careful not to wrap it too tight. If you feel throbbing, or especially if your skin is turning blue, it's too tight. Don't keep the bandage on overnight.
  • It may also help to elevate the place where the bruise occurred. The farther away from the heart it is, the more blood will rush to it, and the bigger the bruise could be. Elevating the bruised spot will lessen the amount of blood that accumulates there.
  • After a couple of days, it may help to apply heat. This will increase circulation to the area, get more white blood cells to show up and take away the dried-up stuff.
  • Some people say that Vitamin K works. Others say to try witch hazel. That's a topical ointment, and since the bruise is under the skin, that sounds like a lot of hogwash to me. Most medical professionals say there's no evidence anything like this has any effect.
  • Most bruises take about 1 to 2 weeks to heal.
  • Very deep tissue bruises can sometimes take up to 6 weeks to heal.
  • Some medications can make you more susceptible to bruises. Those types of medicines include:
  1. Aspirin
  2. Ibuprofen
  3. Naproxen (Aleve)
  4. Cortisone
  5. Asthma medications
  6. Anti-depressants
  7. Blood thinners (Warfarin or Coumadin, etc.)
  • Elderly people tend to bruise more easily because their skin is not as elastic, and they don't have as thick a layer of cushioning fat as they used to. So their blood vessels are more vulnerable to bumps and bangs.
  • Here's when it's time to go see the doctor about bruises:
  1. A bruise gets more painful over time, or is continuing to swell
  2. You're getting several bruises but you have no idea why
  3. You have a bruise near a joint and it hurts to move the joint
  4. The bruise is on or near your eye.

I know you didn't really need to see another photo of a bruise, but I thought this one was kind of funny, because she is smiling. This is Liz, and she got the black eye because she walked into her husband's blind spot while he was enthusiastically playing Zelda on his Wii and he accidentally hit her smack in the eye.
(Photo was from Wii Have a Problem, which seems to have gone 404. Reposted at Jonathan's Blog)

Medicine Net, Bumps & Bruises
TeensHealth, Bruises
Dorland's Medical Dictionary, contusion and hematoma
OneLook, hemoglobin
Wyoming Valley Health Care System, A Closer Look at Bruises
Forensic Medicine UK, Bruises / Contusions, Bruise
Health A to Z, Bruises, Sports Injuries, Bruises and hematomas
Fit Sugar, For Minor Bumps and Bruises Use R.I.C.E.
Net Wellness, Bone bruise, April 25, 2006 Blog, Deep Tissue Injury, September 24, 2008
NationMaster, Encyclopedia, Biliverdin, Bilirubin


  1. If I had a nickel for every Zelda-related injury I'd sustained, I could bailout the banking industry.

  2. Very helpful. Thank you.

  3. I have had a large bruise on my back for over9 months I am on blood thinner and at that time i was also on plavix too. I have a really bad back so I am constintly using my heating pad. i am begining to think that it is perminate.

  4. I am a makeup artist who found this resource exceptionally helpful for an upcoming project! Thank-you for sharing it!

  5. I have a small to medium hardness under a bad bruise I received over a week ago I wonder if I'm going to die. I have stage four cirrhosis of the liver ( the final stage before death)

  6. My bruises no longer hurt nor is the large mass of hardness under the bruise,it's on top of the front of my leg. I've stage four cirrhosis of the liver,the final stage before death. Could this be causing my strange hardening under the bruise? Is it dangerous


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