Spiritually, an injury or scar may suggest that something negative and harmful has occurred, which is an external force rather than internal. We may not have dealt with it as well as we might.... Dream Meanings of Versatile
Material aspects: An injury will suggest a recent hurt, whereas a scar in a dream suggests that there are old hurts, which have not been fully dealt with. These may be mental and emotional as much as physical, and can remain unnoticed until we are reminded of them. Just as in physical injury there can be many kinds of scars, so there can also be in the other areas. We may, for instance, be left with a pattern of behaviour which is irritating to other people, but without the clear connection given by the dream image, we are unable to understand it.... Dream Meanings of Versatile
Vision: Seeing an injury: a warning to be careful when dealing with people or instruments/tools. Here it is important which part of the body has been injured. See Body, Operation.
Depth Psychology: Somebody has hurt you (through an insult, unfairness, or disappointment), and you need to come to terms with it. Or was it you who injured someone? See Bandage, Pain, Wound.... Dreamers Dictionary
Dreams of an injury suggest an overuse of energy and that you are out of balance. This is a red flag alerting you to pay attention and sync up with your natural rhythm. See Accident.... Strangest Dream Explanations