Can any doc tell me what's success rate of spinal surgery?

Depends on what/why: Spinal surgery typically falls under 2 categories: 1) decompression such as discectomy or laminectomy that is indicated commonly for leg or arm symptoms and have a very high success rate; 2) fusion which is indicated for instability (excess motion) or problematic scoliosis or other structural problems. There is great controversy regarding fusion or even disc replacements to treat back pain however.

Individual: It is based upon many factors including: the nature of your spinal condition, whether or not you have other medical problems, the surgery being done, and the relative skill/expertise of your surgeon. Doing the right surgery on the right patient with the right surgeon can have a very high success rate of over 95 percent. Doing the wrong surgery on the wrong patient is unlikely to be successful.