Did you get a microchip? It is always a good idea to have that taken care of. I'm not sure where in the country you are, but you could ask your vet about the leptospirosis vaccine. If your dogs are in lakes and streams frequently it can help prevent zoonotic diseases. I admittedly need to get my dogs back on this vaccine as well.
Also, did the vet check his hips? Large breed dogs usually should have their hips checked here and there.