Some exercises you could do......
Backing - a really good exercise for a pushy horse. All exercises that are done will establish you as the leader, but for some reason this one is said to establish it the most.
Lateral flexion - Good for building the foundation of a very soft horse that doesn't pull on the bit. And this is the beginning stages of creating a horse that naturally wants to travel in a collected gait.
Yielding the hindquarters - making the horses but move away from you is always good. If you've ever watched horses....they will back up into one another with their butt to say, move it or else I'm going to kick you.
Desensitizing exercises - the idea is you want your horse to stand there falling asleep as you are making a ruckus around him. Plus this is a great way to teach your horse to not be afraid of you or any of your tools such as whips, sticks, ropes....whatever else you may use.
Sending your horse between you and an object such as a fence or the side of a building. The goal is to create a gap just small enough for the horse to fit through between you and the object and have your horse just calmly walk through the space......I'm mentioning this exercise because it's one that you can do with a wounded ankle because you won't need to move nearly at all........BUT if your horse isn't quite trusting you as his leader then you may want to hold off on making the gap really narrow or else he may kick out at you in fear.....or just hold off on the exercise all together until he's trusting you, and then start with a large gap and work on making in narrower.
Sidepassing - this would be good and wouldn't require a lot of effort on your part. You will still need to walk a little bit but you shouldn't be hustling around.
I'm just trying to mention a few exercises that you could do with a hurt ankle that won't put lots of stress on you. Though all of these exercises could use some very thorough explanations that could fill a book....and they have.