Can a frontal lobe brain injury cause ms ?

Not at all: There is no relationship of trauma causing ms in any case, ever. Whether certain injuries could worsen ms may be still controversial. The american academy of neurology has a position statement regarding this. www.aan.com.

Probably not : The exact cause of multiple sclerosis is not well understood. However, researchers have looked at a link between brain injury and ms. It is a very weak relationship. About 1 person in 5000 who has a brain injury may get ms, so i wouldn't worry too much about it.