This does not seem to fit in any category below, but I use I use a Fore-arm crutch. I have had it slip out from under me when on wet surfaces.

It is an aluminum design, with a rubber piece on the end. The rubber piece has concentric circles, which are fine on a dry day. One other thing, I have lower back damage that is
"inoperable" per several doctors. I put a LOT of weight on these forearm crutches, so much so that I bent one. Apria said they had never seen one bend before. I weighed about 205 when I leaned on it enough to bend it. I don't use it for balance, I use it to take the weight off my right hip.

I thought about taking a saw and cutting some grooves in it, like car tires. I asked Apria for assistance, but who knows. We can't quit leaving the house when it rains. I have had this crutch slide on all painted surfaces...period.

Any ideas?