- Home
- Parents Home
- Allergy Center
- Asthma Center
- Diabetes Center
- A to Z Dictionary
- Emotions & Behavior
- First Aid & Safety
- Food Allergy Center
- General Health
- Growth & Development
- Flu Center
- Heart Health
- Homework Help Center
- Infections
- Diseases & Conditions
- Nutrition & Fitness Center
- Play & Learn Center
- School & Family Life
- Pregnancy Center
- Newborn Center
- Q&A
- Recipes
- Sports Medicine Center
- Doctors & Hospitals
- Videos
- Para Padres
A to Z: Contusion (Bruise), Knee
May also be called: Bruise
A contusion (kun-TOO-zhun), or bruise, of the knee is an injury to the skin and underlying tissue of the knee.
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 contusion doesn't heal or continues to be painful.
All A to Z dictionary entries are regularly reviewed by KidsHealth medical experts.
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
© 1995- The Nemours Foundation. KidsHealth® is a registered trademark of The Nemours Foundation. All rights reserved.
Images sourced by The Nemours Foundation and Getty Images.