That our rabbit's got a new litter bin, and cardboard box, doesn't mean that his ageing problems are all over or satisfied. He's had arthritis in his back, and growing in his knees. He's been moving more stiffly. At one point we saw he was standing, front paws in the litter bin --- by the tall rim, not the little one --- and hindpaws on the floor. He couldn't get enough momentum to jump in or jump out. (We've since rearranged things so he can't get to that position again.)
bunny_hugger's parents reminded us that the vet was getting a cold laser. They'd tried one out a few months ago --- our rabbit got a couple weeks' treatment --- and thought the benefits were enough to make it worth getting one. It's still controversial; nobody's quite sure why it should work, although there are some reports of it helping larger animals with their pains. The best theory is that the laser light stimulates blood flow around sore spots, and this somehow helps them recover. It doesn't seem like it could hurt, anyway.
So we signed him up for a course of six treatments. He's still not happy to be put into his carrier and taken to the vet, but he's resigned to it and less able to hop away anyway. And they do love him down at the vet's, so there's that. But then after the second visit we realized he was having a lot of trouble moving. He was flopping over as if his right leg were asleep, with no support at all.
By the time of his next visit --- after the weekend --- he was moving about more normally. Stiffly, yes, but not terribly, and not with his feet flopping over. The vet considered, and watched him hopping on the rug too. So this changed the course of treatment a little, with more attention given to his knees. After that time he didn't hop as if sore, nor did he flop over any.
He's certainly getting older, visibly and more painfully. But he doesn't seem to be getting less energetic, or less interested in the world. He just moves less well, and with more evident trouble.
Trivia: NASA received 720 applications for the Group 3 (1963) astronaut class. 492 were from recommended military personnel; 228 by civilians. A total of 490 passed initial screening. Source: Moon Bound: Choosing and Preparing NASA's Lunar Astronauts, Colin Burgess.
Currently Reading: Conquerors: How Portugal Forged The First Global Empire, Roger Crowley.