This is my story:
I suffered a bi-lateral pars fracture of the L5 vertebrae in my teens. I my late twenties I had an S1-L5 fusion with no instrumentation (plates & screws). Fusion did not take. In my late 50's I had a ALIF (anterior lateral inter body fusion). They go in through the front. The fusion was successful but unfortunately my symptoms of lack of stability and soreness and ability to play golf/tennis etc remain. I realize every case is unique and it is difficult to draw general conclusions. If I could turn back the clock, I would have decided against the surgeries. If possible get as many opinions as possible both orthopedic and neuro surgeons. I manage my pain by religiously swimming, fitness center doing exercise bike/EFX 6 days a week but of course I'm disappointed I didn't get the result I wanted. Remember I've heard but never read any studies confirming that 1/3 of back surgeries are a success, 1/3 cause no harm but are not effective, and 1/3 result in being worse off. Best of luck and I wish you the best.