I'm just an amateur. I play piano for fun. I also enjoy communicating on the internet with a QUERTY layout keyboard, on which I can type faster than I can talk or listen. So I really value my hands.
I don't play football, basketball, or hard baseball. I don't use a chainsaw. When doing woodwork, I mostly use a sabre saw which is pretty non-threatening, although I do own a 7" disk saw. When using power equipment, I do a lot of thinking about risk. If something was to slip, where is the hand or sharp edge going to go? Is that an okay place? Safety planning involves planning for failures and mistakes.
When I hook up the tractor to implements, I use 16" channl-lock pliers instead of my hands in the pinchpoints. When my bicycle chain falls off (18 speed this is pretty frequent) then I use two screwdrivers and maybe a slip joint pliers, instead of my hands, to untangle it. I don't own any chain drive farm equipment, but if I did I would follow the same procedure on the pinch points. I had two co-workers cut fingers off with chains and sprockets, in 8 years of employment as a maintenance worker. Both were sewed back on. Both sort of work, but not good enough for piano or 9 finger typing.
I'm helping a pipe organ voicer install a PO, but don't use the power drill to install screws, as it makes my hands hurt at night, the joints and tendons. I turn the screws by hand, much slower. His hands are much bigger than mine, and even though he is three years older he says screw tighten shock doesn't hurt him.
Also watch using hands as hammers, there are a lot of shock damages that can be covered up by testosterone in one's prime years, but the pains come right back as this dries up in the fifties or sixties. Read the side effects of male hormone therapy before believing the results of the ads, we have free speech in this country (USA) but a lot of commercial speech is stupid speech.
Read OHSA literature about pinch points, and think about them when working around things. Even car doors, I've been pinched by doors I was pulling myself, and now vans and things have power doors that could really do a job on you.
Piano is great fun, but ten fingers makes a lot better music than nine or five, IMHO.
For the disabled, there is always organ pedals, which require only two feet, but you can only play four notes at a time that way.
Oh, and for the boxers etc above, I do work out. Mostly aerobics, the low impact kind since the US Army removed the cartledge from my knees. A lot of miles on a mountain bike, 70+ a week in the summer. Tree removal in the summer without chainsaws ( unproductive but strength building) and upper body resistance (bands) and weight training (5 lb) in the winter. situps and pushups. Use it or lose it, at my age, and stories about people being stuck on the bathroom floor for 24 hours waiting for their son to come by (personal acquaintance) are incentive enough for me to keep the big muscles toned and bulked up.
Topic: How careful should a pianist be about his/her hands?