Haley is absolutely right. You will not only want to restrict your bunny from higher cage levels for a bit, but you may also want to limit his jumping access for a while. That is not always easy, but until things are really healed it is necessary.
Our vet says that the thing he sees bunnies for most in his practice is spinal injuries. He discourages the use of ramps and shelves in a cage or play area unless they can be covered/coated with slip resistant material.
Hope Dory continues to do well!