Sometimes my toes hurt. would this maybe be an effect of my old spinal injury?

Not necessarily : If you have nerve problems from your back you should have pain traveling down your leg to your toes. If it is just your toes it may be something else.

Maybe: If the problem was present at the time of your spinal injury it may be a continuance of the problem... If the injury was long ago and the toe pain is recent it is probably not related.