Unless there is an unusual circumstance, I would expect the success rate to be lower. The procedure called vertebroplasty inserts a balloon into the fractured vertebrae, blows up the balloon to re-establish the height of the bone and then cemented. It is done for pain control, but I would expect that the fractured bone has already healed in 3 months. Talk to his doctor. Also see Archives News section on this site for a review of a research article.
My dad was in a car wreck July 10, and was diagnosed with a fractured vertebra. He recently has been told he would need a new procedure to correct the problem. He will be having the balloon procedure done. With the surgery being delayed for 3 months, will the success rate be higher or lower?