Hi!
I also have this at the L5/ S1 level, and I am also fairly young... 27, too young to be considering a major back surgery anyway!
My slippage is not as severe as nscrbug's, but I am actually in a lot of pain, and do consider myself somewhat disabled. I have Grade 1 spondy, although I am almost to Grade 2. My slippage is about 20%.
My pain started back in May (6 months ago), and I suspect it has something to do with having an infant. She is now 13 months old and 25 pounRAB.
When it started, it felt like I had a knot in my groin area. It only bothered me when I stood up or bent forward. Since then it has progressed to be excruciating at times. The pain is always there, but it intensifies as the day goes on. I now feel it in my lower back, left groin, and left leg. Some days it is in both groins and legs. I also experience nurabness on my left side. I have been missing work, and I need help in the evenings with my daughter. (My husband works evenings). After visiting my family doctor several times with no luck, I finally went to urgent care because I couldn't take it anymore. They did an x-ray and diagnosed me. This was only a few weeks ago. I have since had an MRI, which confirmed the diagnosis, and am in the care of an orthopedic doctor. I should also mention that I have no other issues happening, like a disc bulge or herniation, so the Spondy is 100% the source of the pain. I am taking norcotic pain killers everyday (OTC stuff does nothing for me) and I am having a steroid injection on Tuesday. This should hopefully calm the nerves down and offer some pain relief. I am also considering Spinal Fusion surgery. Spondy can be managed to some degree with meRAB and PT, but it can't be corrected without the operation. I still want more babies, and I don't want to deal with this forever, so surgery is seeming like my best option at this time, especially because I am in so much pain.
The surgery is a nasty one however. They fuse the spine where the Spondy is occuring, to correct the slippage and allow the pars fracture to heal, and it takes a long time to recover. I would need to miss 3 months of work at least, and it can take a full year for your body to fully recover.
For me, the only thing that brings me relief besides pain meRAB is rest. Unfortunately I don't get to rest very often. I work full time, and my husband works opposite hours from me and is a full time student, so I am usually alone with my daughter, and she requires a lot of attention.
Please feel free to ask any more questions! I am still new to this, so am not an expert, but I have done a ton of research so I might be able to help.
Good luck to you and your daughter!