Have you tried lidocaine patches (http://www.endo.com/patients/products/lidoderm.html)? I saw a recommendation for them on fibromyalgia a few months ago and asked my doctor for a script for them. They are marvelous! The first time I tried them I had bilateral back pain sort of halfway down, bad enough that my usual dose of Ultram wasn't doing enough, so I got K to put on a couple of patches, one on each side. Wow! It eases the pain for 8-12 hours, and by the time the effect wears off the reduced pain is easier to control (since it's always easier to keep pain from getting bad than it is to control pain that's already severe).

They come in a package of 30, and you can cut them to fit (http://www.endo.com/patients/products/lido_faqs.html) your foot and use up to three at once (e.g., two on your shoulders and one on your foot). They really do help -- ask your doctor if you can try them.