I put trekking bars on my mountain bike after I developed arthritis in one of my wrists. I was able to use the same brake levers and shifters. There are many more positions to put my hands, which suits the arthritis just fine.

I also bought a set for my road bike which has drop bars. I've assembled the other things I need for the conversion: 9-speed XTR trigger shifters (to replace the Ultegra STI shifters) and Paul brake levers. I haven't made the switch yet because the drop bars don't bother my wrist as much as I thought they would. Maybe I'll build up an old steel bike and use them.
Steve