I've had problems with both of my big toes for about 10 or more years but not as much as I did a while back. I usually get a pain in the bottom part of my foot or no pain while I'm just walking or laying down and then my big toe will pop outward and I can't move it and it's very painful. The only way I'm able to get it back in place is if I squeeze my hand around all my toes and keep trying to get my big toe back in place again. I would have went to the doctor when I first started having this problem a lot, but my mother didn't believe me even when she seen my toe messed up. I haven't had much problems with my toes for a while since I use to wear shoes all the time since that helped the problem from occuring. I haven't been wearing shoes as much and I'm starting to get the pain in the bottom of my feet like it's about to go out of place again. What could be the cause for this or anything that might help it from happening?

I have a similar problem and wonder too! (with the big toe)
I think it somehow gets dislocated - maybe tendons pulling on it?
Do you have anymore news on it?