Chris,
I have had similar jerking for years, and hsve also been told that they did not indicate an underlying problem that they normally occur when going to sleep. Normally I would also hiccup once in addition to random body jerks. Later, I had the hiccups from early evening until late afternoon the next day. When I told my neuros about this, they said there were too many causes for hiccups, and my condition was not worth investigating.
Well, of course it wasn't worth their time, they were not hiccuping. Eventually, the jerking and hiccups went away. I take a number of antiseizure meds, and I guess they now prevent the jerks (no, i not referring to the neurologists I saw, even though they were jerks.)
Like most neurological problems, you hve to keep seeing a new before you get help.
I spent eight years tracking down my disease, cadasil, which affects 400 families worldwide. I have never been to a doctor who has treated someone with cadasil before, but maybe that was fortunate for me, who knows. My seizure problems were solved after a year of falling...it ended up being a blood pressure problem.....not being able to pump enough blood to my brain due to damage to valves from diabetes I think.
At any rate, given the severity of the symptoms I have, from vascular dementia, to peripheral nerve damage, and so on, I ignore the minor problems my body has, and would suggest you do the same thing. Or try to, at least; you never know what is coming next.