Without examining you I can not determine where the problem is. This could be a problem with a peripheral nerve, such as the common peroneal nerve, or a problem in the lumbar spine. What I would recommend, since you have a trip coming in the future, is that you travel to a large academic center for a second opinion. I would recommend seeing a neurologist who specializes in neuromuscular disorders. They will be able to review your exam and testing and then make recommendations. I wish I could provide more information, but your examination is essential to generate a list of possibilities. Good luck.