I'm not climbing hills yet since they aggravated the low back so badly, but I'm up to a whopping 20 miles of bike path (which is 3+ laps of the nearest one ). Better than nothing.
I've had my own issues with climbing aggravating back/neck injuries so I feel your pain on this one. It IS, however, wonderful that you can get out there and ride - sweet! It will surely just go up from here