An injury is damage to part of your body, usually caused by an accident in the home, on the roads, or during a game, e.g. of football. Here are some common injuries:
Look carefully at the key words in these texts.
John fell off a chair, hit his head on the floor, and knocked himself unconscious. His wife called an ambulance but John was still unconscious when it arrived. He was rushed to hospital (= taken very quickly) where they kept him for two days for blood tests.
I jumped for the ball and collided with another player (= we ran into / hit each other). We both had cuts on our head, but I had to go to hospital for eight stitches.
Wounds and injuries
Wound (n, v) and injury are both used to describe damage to the body, but a wound is generally caused by a weapon (e.g. gun or knife) and it is usually intentional.
He shot the man in the chest. (= a bullet wound in the chest) [from a gun]
He stabbed the boy in the back. (= a knife wound in the back)
He got into a fight and got beaten up. He had a black eye and two broken ribs.