Difference between Hematoma and Contusion

What is the difference between Hematoma and Contusion?

Hematoma as a noun is a swelling of blood, usually clotted, which forms as a result of broken blood vessels. while Contusion as a noun is a wound, such as a bruise, in which the skin is not broken; often having broken blood vessels and discolouration

We hope you now know whether to use Hematoma or Contusion in your sentence.