Is it malpractice if the doctor implanted generator on spinal stimulator in the wrong place and pinching sciatic nerve has to be redone?

It sounds like malpractice; contact some medical malpractice attorneys but if the pain has disappeared then the case value is probably too low to justify a lawsuit [need an expert opinion that there was malpractice, will need expert testimony, filing fees, subpoena of medical records, etc.]

It takes a medical expert to answer your question. Medical malpractice lawyers typically have such experts available. Consider consulting one. Good luck.

You would have to have expert witness testimony from another surgeon to prove that the procedure was done improperly. It could be done, but is never easy.

Medical and dental malpractice claims are, by their nature, very difficult. Under California law, it is necessary, before filing suit, to obtain an affidavit from another professional, verifying that he has reviewed the medical charts and has found that there was negligence. This can cost several thousand dollars, and most attorneys expect that the client will cover this cost. Negligence could be defined as the failure to use REASONABLE care; not all bad outcomes are the result of negligence. You should also be aware that there is a cap on the amount of recovery for pain and suffering, thanks to the doctor lobby. Sometimes one has a good case theoretically, but the damages are too small to warrant a suit.