Hi! I broke my back in 3 spots after a fall off my horse(this was back in January and I'm now healed yay! Started riding again about 2 weeks ago) BUT ANYWAYS during the almost 6 months that I couldn't ride these are things that I did with my horse!
-took him on walks (just like a dog aha, horses are curious animals and love getting to see new places, plus any time spent with your horse is bonding time so they will love that you are there!
-I would bring a lunch or a snack to the barn and I would just sit on the ground next to my horses stall while I eat and just talk to him, like I said any time spent with your horse is bonding time and they really do enjoy you being there.
-you could also go in the arena and try running around or kicking a ball or dancing and it may seem weird but your horse might start "playing" with you
I hope this gives you some ideas!! I hope for a fast and easy recovery for you!