Something else to consider. Posture.
I used to experience sufficent shooting, sharp pains through my thighs to bum cheeks that caused me to leave my Boeing seat in order to releive the pain. Cramps? Not really, but I was in pain every 20 minutes or so.
Went to the Doc, and he said he'd seen this all before, particularly with Farmers who drive tractors for long hours. After bending me like Gumby for some time, he told me to alter the seat position in the aircraft I then crewed. Lower the lumber support to it's lowest position and keep the seat back totally erect at 90 degrees.
My problem was then fixed.
Hope this offers some help.