spastic movements when relaxed

Hello. I am trying to help my husband figure out what is causing his spastic movements when he relaxes. He has always been a jumper when falling asleep. I think all of us have at one time or another started to fall asleep and then jerked or startled awake. However, in the past three weeks, he has taken it to a new and frightening level. whenever he is relaxing or trying to fall asleep, his body starts to jerk spastically again and again. This can go on for an hour! He can' t seem to control it and it is freaking him out.
On a side note, he has had a pain in his back for   2 1/2 years of and on. It has increased lately and he has felt a little lump above his buttock. He had an MRI and it is an unexplained nodule. He's been exhausted and when he went to the doctor, she said that if he were a woman and in his 20's, she'd be concerned about MS. Well, this got him freaked out and her researched MS and started thinking he had it which caused him to have a bit of a meltdown at work adn he ended up in the ER. He had an MRI and an MRA on his head and they came out clear. He was relieved about that but is still having anxiety attacks especially over these spastic movements. he went to a neurologist who didn't seem concerned at all and scheduled an EEG more as a way to appease my husband than for a diagnosis. My husband is planning on having the nodule removed but still can't seem to calm down and sleep. The doctor put him on Ambien to help him sleep which helped one night but the next he only slept for 4 hours and then worried about his lack of sleep. He has never been this way and I am worried. He did tell me that when he was in his early 20's he had a few panic attacks but never these convulsive movements.
Does anyone know anything about these movements? I have encouraged him to see a therapist about the anxiety and he is willing but no one seems to be able to diagnose the convulsive problem. HELP!

[KatEyes]

There are different rythmic movement disorders, and one that is during sleep is Periodic Limb Movement Disorder. It generally involves the feet and legs but sometimes involves the arms, head, or trunk. Has he had a sleep study so the movements can be recorded and also compared to his brain waves at that time?

Has his neurologist witnessed his episodes? If no one has seen them, you could videotape them yourself and ask the doctor to review the tape with you. Diagnosing movement disorders can be a process when the obvious have been ruled out. Try to reassure him that the answers will come, and till then he is best off by finding ways to help his anxiety over it. Just seems that could exacerbate the symptoms.