Bruising is caused by the rupture of blood vessels under the skin. Slowly, the blood decay and be absorbed. When this absorption occurs, the blood loses oxygen and turn blue. Then, bruises turn green, yellow, and finally disappeared.
Bruising can cause pain, but generally not dangerous. Bruising can sometimes lead to serious consequences, leading to a more threatening form known as a hematoma and may also be associated with other more serious injuries such as broken bones or internal bleeding. Small bruise easily recognizable because of the characteristic blue or purple a few days after the injury.
Pain in the usually mild to moderate bruising and swelling that accompany moderate to severe. The bruising that may occur in the head, shoulders, elbows, hands, chest, abdomen and legs. Hard knocks to the head can lead to bruising and possible cuts