Hello, I am a 42 year old with history of L5-S1 PSFI almost a year ago.  Symptoms are still present.  Back pain as well as left hip bursitis and pain shooting to my left knee and sometimes down to the shin area.  I saw my surgeon who is concerned that I may have an issue with the instrumentation.  Not infection, rather my body "not being able to adjust to it".  I had a CT scan recently which showed the following: Mild anterior positioning of L5 on S1, minimal spondylosis along the anterior disc marging of L2-L3, moderate diffuse disc bulge at L2-L3 with additional posterior midline disc protrusion at L2-L3 indenting the thecal sac.  Any thoughts?
Dear patient First why L5 s1 fusion was done? Was it for displacement of L5 on s1 (listless)?  Considering your present symptoms' possibility of disc prolapse with nerve root compression is more likely. Your CT scan report is showing disc prolapse at L2L3 level.  Displacement of L5 on s1 is known as spondylolisthesis and is due to instability. I would advise MRI of lumbosacral spine with screening of whole spine as MRI is more sensitive and specific for diagnosing disc prolapse. All the best. Visit expert spine surgeon with MRI report.