A few years ago, i suffered an injury that left my left hane unable to work a clutch.  Is it possible to get a clutch modified so you can operate it by some other means like a foot pedal or something?  

Depending on your bike, a foot/rocker clutch should not be to hard to improvise, as long as you could shift using your clutch arm.  

http://www.pingelonline.com/index.htm They make air shifters that do not require a clutch to shift. You will have to find a foot clutch operation, I would think, so that you can shift into neutral at a stop. There are many companies that make foot clutches. I have even seen jockey shifts that you can use a foot clutch on the left foot, and shift with your right hand. You do not say if you have no movement in your left hand, or just partial movement... either way, a foot clutch might be the answer...  

I just found this website and thought it might be something that can help you.

www.revloc.com

I considered it for myself....just to eliminate the long time the clutch is pulled in  at some of these long red lights here in California.

good luck.