I have a 4 year old son with a forearm bruise – about 2 inches in diameter with a somewhat raised white bump in the middle. This bump feels like a small hard nodule and can be moved around a little under the skin . I seems to be deeper than the dermis, possibly epidermis. The nogule is not deep enough to involve the muscle. He has no fever and does not complain of pain in the area when I push on the bump or the surrounding bruised tissue. Our pediatrician diagnosed simply as a bruise. I ve banged myself up many times and have yet to run across a bruise like this.