Cat has twinges and spasms.

I have e a six year old female persian that was a former show/breeder cat that we adapted over a year ago. Before we adapted her, the breeder had her spayed. When she woke up from the anesthesia she bit her tail hard enough to draw blood and require stitches.
We have noticed a strange behavior on and off since we got her where she will go from very calm to very nervous. For instance, she can be laying on her lap with you petting her seeming very calm and will all of a sudden take off running like a streak, often looking back like something is attacking her from behind. When she stops, her muscles in her lower back will twitch back and forth. You can see her fur moving. She will sometimes bite her tail but not draw any blood. This behavior usually only last less than a minute with no loss of balance or what would appear to be seizure like behavior.
Just my wife and I and two other male cats live in our house so the atmosphere is pretty quiet and relaxed. The other two cats have not shown any of these symptoms and she does not appear to be bothered by the presence of the other two cats. They are all Persians and get along well.
When I play with her with the laser light, she chases it around with no signs of any discomfort in her joints. She is a small cat, about six to seven pounds that gave birth to quite a few other Grand Champion kittens.
I have thought about taking her to a animal chiropractor that our son took our basset hound to for low back and rear leg problems with very positive results. The chiropractor is about three hours away. The fact that she is a small cat and was used for breeding makes me think that she could have some issues in her lower spine from giving birth. Because she does not have the symtoms most of the time and otherwise acts very normal makes me think it could be caused by something else.
She has been to the local Vet for a wellness check and when I explained her behavior to the vet, she didn't really have an answer for it. Our cats are very well taken care of and are fed a very good quality food.
Any advice on this would be greatly appreciated.
Thanks!

It could be Feline Hyperesthesia Syndrome also called rolling skin syndrome and skin twitch syndrome.  Here is an article on it http://www.veterinarypartner.com/Content.plx?A=2873   A google search will bring up more articles.  There are varying degrees of severity.  There is no cure for it, they are really not even sure what causes it.  There are some environmental things that can be done which are geared at lowering stress some of which are listed in the article.  There are medications which help, also discussed in the article, but your kitty doesn't seem to have a severe case so I don't know if medication would be warranted.

Thank you very much for your reply. I will have to read up on it as soon as I get a chance. She is the sweetest little cat otherwise.