DoI had an L5/S1 Spinal Fusion in May 2014. Diagnosed with spondylolisthesis, 3 bulging discs, 2 herniated discs and degenerative disc disease. I was subsequently placed on 60 days of Con Leave and did physical therapy sporadically. I essentially rehabbed myself over a 4 month period. I had an awesome chain of command that had my back and let me do my own thing during that time. At the 5 month mark afterwards I was doing an APFT and ruck marching again. It is possible to come back from the spinal fusion, depending on how bad you want to stay in. I am in a constant state of pain, significantly less than prior to the surgery but still stiff every morning and in need of doing an extensive warmup prior to any type of running/ruck/deadlift exercise. As far as my job, I've been a 1SG for the past 3 years in an Infantry Company and do everything my guys do. My advice would be just to take it slow and easy and listen to your body. If you have any other questions let me know and I'll be happy to answer them.