May also be called: Bruise A contusion (kun-TOO-zhun), or bruise, of the buttocks is an injury to the skin and underlying tissue of the buttocks. More to Know A contusion, or bruise, forms when soft tissue in the body is crushed but the skin doesn't break. When this happens, blood from broken capillaries (small blood vessels) near the skin's surface may leak out under the skin. With no place to go, the blood gets trapped, often forming a red or purplish mark that hurts when you touch it. As a contusion heals, it may turn different colors, from red and purple to black and blue and then to green, yellow, and light brown before fading away. Keep in Mind Applying a cold compress to a contusion may help minimize swelling and bruising. Seek medical attention if a bruise continues to be painful. All A to Z dictionary entries are regularly reviewed by KidsHealth medical experts. Back to Articles Related Articles A to Z: Contusion (Bruise), Abdomen Learn more about contusions (bruises) of the abdomen. Read More A to Z: Contusion (Bruise), Back Learn more about contusions (bruises) of the back. Read More A to Z: Contusion (Bruise), Chest Learn more about contusions (bruises) of the chest. Read More A to Z: Contusion (Bruise), Hip Learn more about contusions (bruises) of the hip. Read More Word! Bruise When you bang a part of your body against something, your skin might turn different colors where you bumped it. Read More First Aid & Safety Center Boo-boos, bug bites, and broken bones - oh my! Here's your one-stop shop for everything you need to know about how to keep kids safe. Read More Bruises This article is all about bruises, including why they happen, how to make them go away faster, and why they turn all those funny colors. Read More Dealing With Sports Injuries You practiced hard and made sure you wore protective gear, but you still got hurt. Read this article to find out how to take care of sports injuries - and how to avoid getting them. Read More First Aid: Falls Although most result in mild bumps and bruises, some falls can cause serious injuries that need medical attention. Read More First-Aid Kit A well-stocked first-aid kit, kept in easy reach, is a necessity in every home. Learn where you should keep a kit and what to put in it. Read More Quadriceps Contusion Quadriceps contusions are common in sports that have a lot of direct contact or a chance of collisions or wipeouts. Find out what to do if you get one - and how to avoid them. Read More What's a Bruise? Have you ever had a bruise that turned a bunch of different colors before it went away? Find out why in this article for kids. Read More Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. © 1995-2021 KidsHealth®. All rights reserved. Images provided by The Nemours Foundation, iStock, Getty Images, Veer, Shutterstock, and Clipart.com.