Herniated l5-s1 herniation post l5-s1 laminectomy w/ fusion, why can't I be surgically treated when all has failed?

Vague question. Assuming you mean why _further_ surgery is not advised (the laminectomy & fusion certainly are surgeries!) there may be many factors including general health. However, i would suspect that scar tissue formation around nerves in the area of prior surgery may be so intertwined with the nerves, matted down, that one might easily damage the nerves trying to take away the scar tissue.
Surgery possible. If you have had a fusion and some of the disc remains and reherniated to cause your current symptoms and you have imaging that correlates, surgery is possible to relieve the pressure on the nerve. The other question a spine surgeon would try to answer is whether or not your fusion healed. An evaluation by a spine surgeon will be helpful.

Related Questions

After having a failed laminectomy w/ spinal fusion @ l5-s1, what can't they surgically fix the area?

Failed back syndrome. Failed back syndrome (FBS) can be caused by many different factors. Laminectomies, in particular, have been shown to result in spinal instability in biomechanical studies. Minimally invasive surgery (mis) can help obviate some of the complications associated with fbs. Unfortunately, there may not be a quick fix in your particular situation. I would obtain a formal consult from a spine specialist. Read more...
Lumbar fusion. Failed can mean alot of things. Is it that you are not happy with the results? Or is there still a problem that is operative, i.e. Adjacent level syndrome at the level above the fusion or did the fusion not take at l5/s1 and there is a nonunion. I'm sure that your spine surgeon has discussed this with you. Read more...