I have had arthritis in my hip since a bad car accident when I was 16. About twenty years ago, there was a really bad flare-up that led me to buy a cane to keep around. I remembered my Hapkido instructor in college was big into using the cane as a weapon, and shopped around.
I bought a Gentleman's Cane (in hickory heart) from Canemasters.
Cane Masters Custom Canes for Self Defense and Fitness, Best Custom Canes and Self Defense Systems
My arthritis is infrequent, but I often use canes for the hiking I do here in the mountains. And I've taken them on trips to NPEs (pinko cities and countries, on airplanes, into prisons, court houses) when I've had arthritis issues. Canemasters also do trainings and have many DVDs and such, but I've found that most folks would do fine after taking a look at any number of the books that I've bought since then - a favorite is Bruce Tegner's
Stick Fighting: Self Defense which is sometimes hard to find cheap but presently is listed used on Amazon for under $14 delivered.
One reason to read these books is to figure out retention - there are some reasonably easy things to do that will make it very difficult for an assailant to get your cane from you (to use against you). They show reasonably simple strikes as well as more complex ones (that I think are pretty silly for an older fellow). The basic benefit of the cane is that it allows you to get mobile, which gets you in better shape and improves your balance out in the world so that you look less like a victim. Additionally, you are holding a yard-long piece of hickory, which encourages them to find another target. (I like dogs fine but I'm always amused at how other hikers get serious about calling their misbehaving dogs to them when they spot my cane - it's not anything
I'm doing, it's that they know I can beat down their dog if it jumps on me. Which I almost certainly would
not, but their sudden realization that their dog's behavior might be an issue is always amusing.)
Anyhow, I agree, be realistic. But if you're fit, this could be a useful tool.