For the past two years my wife (Age 47, 5'3", 140lbs) has had painfull attacks in the back of her knee that she describes as feeling like electric shocks. Many times these are so painfull that they bring her right down to the floor where she screams and/or cries out in agony. There is no pattern of when this happens. They are very random and can occur when she's sitting, walking, running or laying in bed. They also can occur once in a day or week, or several times in the same day. She has had ultrasounds, xrays, mri's, vein tests, nerve tests, etc., and no doctor yet has diagnosed her problem. It scares the heck out of me sometimes because it comes on so quick that there is a violent jerk reaction followed by cries of pain and agony. The location of these painfull electric shocks is in the back of the knee about an inch or two below where the knee bends. We've already checked on it being a Bakers Cyst causing the problem so I don't think it's that. Because of the electrical-shock like nature of the pain, I'm guessing it has something to do with a nerve or vein being squeezed or pinched. But how does that exlplain painfull attackes when she's laying completely flat or in a recliner and not moving a muscle? I should add the she is a nail technician and sits for periods of time with her legs crossed. But she has had a vein test and everything came out normal. She does take B12 shots because at time she is deficient in Vitamin B12. But that doesnt' seem to help. She did have injections of botox which helped somewhat but not a whole heck of a lot. We are at a loss for what is wrong. The Dr's. are at a loss. We've been to 5 or 6 specialists and my wife is at wits end. Any suggestions?