Naaahhh...... Perhaps it's just too much money in your wallet causing it to compress the sciatic nerve, resulting in leg and hip pain.
Seriously though, even though I don't have the same coach, I also have the same problem. I always attributed it to not having enough room to fully extend my leg occasionally while driving just as TiffinUser mentioned. I don't have a "real" fix but have learned that I can minimize it by adjusting my driving times to allow myself a couple of minutes to walk around a little every 90 minutes or so. (Besides, at my advanced age, I have to stop about that often to pee anyway, so it's a win-win situation!!)