My Dr, wants to do a fusion of my bottom 3 vertebra L5 4 3, those 3 are curved, I have had laminectomies on 4 and 5 previously. I am 58 years old and work in construction. I am concerned I will have loss of motion that will preclude me from working and maybe I should hold off until pain is unbearable, What is prognosis for this type surgery?