Bruises in children who do not usually get bruised:
(1) bruises in a baby
(2) bruises in a child who is not independently mobile
Unusual features for a typical bruise:
(1) bruises that are not located over bony prominences
(2) bruises on the face, back, abdomen, arm, buttocks, ears or hands
(3) bruises that carry the imprint of an implement
(4) bruises that show the imprint of a ligature
where:
• The list of sites indicates that bruises on the legs or feet are not indicative unless they meet other criteria.
• Bruises to the arms would seem to be common in an active child.
Multiple bruises:
(1) in clusters
(2) with a uniform shape
I would think that the presence of bruises mixed with other injuries (such as burns) might also be suggestive.
Differential diagnosis:
(1) falls from swings or other play equipment
(2) fights with other children
(3) sports injuries
(4) falls from bicycles, skates and skate boards