Bruises

A bruise, also called a contusion, is a type of relatively minor hematoma of tissue in which capillaries and sometimes venules are damaged by trauma, allowing blood to seep into the surrounding extracellular space. Bruises can involve capillaries at the level of skin, subcutaneous tissue, muscle, or bone. Bruises may be referred to by size as ecchymosis (1-3 cm), purpura (3-10 mm), or petechia (<3 mm), although these terms can also refer to internal bleeding not caused by trauma.