Do you use a prosthesis at all? I think that might be the way to go. As long as you have some way to manipulate the controls reliably I dont see how the FAA could stop you. Most 121 aircraft do require some muscle to be applied to the controls on landing. Different models of the emb145 require lots of backpressure after your mains touch to prevent the nose from de-rotating too quickly. Embrear RJ's have a ram horn yoke that utilizes different muscles in your forearm when applying crosswind correction compared to a vertical, post yoke found in the CRJ and most corporate jets. With a prothesis I dont see why it wouldnt be possible. It could possibly be even easier to manipluate. In the future it seems that aircraft design is going to a sidestick in the cockpit which I would think would be even easier for you. The bombardier c series and possibly the MRJ are going to be side stick in the coming years.

The only problem i see is getting the prosthesis approved by the FAA which i am guessing would entail a lot of jumping through hoops. I would look into AOPA or other aviation groups that probably have had prior experiences with the FAA. There was a group on long Island called Able To Aviation and i think they were out of Farmingdale airport but they specialized in spinal cord handicapped pilots. Very nice guys but it has been a long time since i have seen them around.
Good luck on the checkride and if the FAA gives you any guff... welcome to aviation!