Profiles' 145mm crank arms

The problem people seem to have is that they don't gear down accordingly.

The ghost of Sheldon Brown remains the most useful guide:
http://sheldonbrown.com/gain.html

I rode 72"/140mm and 90"/175mm for comparative purposes, i.e. precisely the same gain ratio. If you're using a normal urban gear of 65" on 165mm cranks, you need to go down to 57" on 145mm cranks, otherwise you've effectively increased your gear and will find you have to press harder on the pedals at any given speed, which is unlikely to be kind to the knees. Note that even this reduction in gearing will still leave you pedal force unchanged, although the reduced range of movement may be beneficial in some circumstances. Conversely, the increased pedalling frequency could just as easily be a detrimental influence on other joint conditions. In other words, consult your doctor before trying to fix joint problems with changes to your cycle equipment.