My 7month old son is always bumping his head? Can this cause development issues?

He is always hitting his head in his crib. Of course i have bumper's all around his crib, but when he goes to stand up he hit's his head on the railing..Or when he is standing he will fall over and bump his head, or when he is crawling around he will go to sit up and bump his head on the wall. He's a boy and i know they are ruff but im worried this can cause him development problems down the road?