I wish I could provide you with an accurate diagnosis, but I can not do that over the internet. It seems that this has become a major concern in your life. When this happens I recommend that patients recieve an expert second opinion. This will help to answer the question and allow you to proceed on the correct path. I would recommend that you make an appointment at the closest ALS center for consultation. If you are in the area, Dr Eric Pioro is our ALS specialist, and he is fantastic. Good luck.
I do have ALS and what you are describing does not sound at all like als...ankle instability is weakness and where muscle have wasted away..........you don't normally get pain with Als...and if you do suffer pain it normally happens at the late stages.
Hope this helps.
Stacy Martin
Stacy