I have been experincing cramps throughout my body. They usually happen in the trunk of my body, but also they have been in my legs, ankles, arms and even in my jaw. I have no idea what brings on these symptoms. If I sit down in my car, or get surprised, laying down in my bed, any sudden movement may cause my body to cramp up. The cramps usually last about 5-10 mins. I have these cramps about 1 week out of the month. My Dr. have not been able to find the cause.