Any injury or side effect can take place after an athlete has been playing their sport for such a long time. However, only time will tell. Some people probably get back spasms as a result of swinging a baseball too much, but others don’t. I suspect that some baseball players do not have back spasms because it depends on how the baseball player holds and swings his bat. If the player is used to bunting the ball, I don’t believe he would get back spasms.
Also, it depends on how well you take care of your back and listen to your trainer and team doctor. If you follow what he says, then there is less of a chance of getting those spasms.