Sorry about your husbands broken ankle - I feel his pain! I have broken mine before, but most recently sprained it pretty bad before our recent trip to CSA. I had graduated from the boot to an aircast shortly before we left. I was able to hobble along just fine without it on when I was going to get in the pool, etc. We didn't do the catamaran cruise this time, though. I would imagine anything that requires climbing steps (like you do to get on the boat) would cause a little bit of a challenge for him.
However, if he is doing PT, being in the water and walking in the sand (without the boot) is the BEST PT he can do for it! I did a lot of my exercises for PT while I was in the pool and I came home without needing my air cast any more! So, while it will be a pain to take the boot off and put it back on, your trip couldn't come at a better time as far as helping his recovery.
Also, if he is wearing the embolism sock to help with swelling, make sure to take extras and wash them out. They will get stinky because you're sweating so much while you're there. Gross, I know, but just wanted to warn you.
I did ice my foot a few times while we were there as well. I took ziplock baggies and filled them with ice that's available in the room.
The rum will also help ease any discomfort he may be feeling. Enjoy!
Melea & Joseph
CN - '06, '07, '08
CSS and CSA - '09
CSA - '10