lessie, your L5-S1 disc has expanded it's bulge. Now it is making contact with the S1 nerve root. The expansion has reduce the space between the joint (facet) facet where the nerves exit the spinal canal enough to cause arthropathy (joint disease which in your case is reduced space and maybe some inflammation probably pain) https://www.totalorthosportsmed.com/what-are-the-symptoms-of-l5-s1-nerve-damage/
You might consider minimally invasive microdiscectomy and/or facet radiofrequency.
I hope you aren't in pain.