Has anyone had a L5S1 fusion from l4 to l6 done and had complications?

I had mine done back in 2010,was ok for 18 months but unfortunately now with heavy severe pain and off drugs due to getting hooked,I stopped taking them over a month ago.I am desperate to have this situation resolved as it has totally turned my life upside down, a family man with two teenagers and a wife.housebound due to severe pain.waiting on the bone scan result and hopefully a meeting with the surgeon.had the mobility car till dec 2013 but that was taken back by DWP due to a bungled ATOS assessment, pain is so bad in flood of tears and really down, unable to work due to the severe crippling pain in my back and love right leg that is permanently numb.