see if someone can make you a version of the Quilter's Slidelock or buy one. Your arm would be well away from the fabric. Or see if a quilting friend with an accuquilt or sizzix would cut some fabric for you.
I had surgery on a wrist/thumb and I was able to use my slide lock. I also bought a Martelli Quilting Halo. I could just hold the gripper between thumb and first finger and was able to play with free motion quilting.
If you lived close enough to me, I'd help you cut.