I'm not a lawyer. To the layperson, it seems it's entirely possible a mistake by the surgeon who performed your discectomy caused your condition to worsen. If that's found to be the case, I would think you'd have legal recourse to sue for damages (lost earning capability, lost wages, medical bills, etc.). Additionally, if your peroneal nerve palsy was directly caused by your positioning during surgery, you may have additional grounds for a case.
Since I am not a lawyer, the only way to be entirely sure about your potential legal options is to consult with a medical malpractice attorney in your area. By sharing your complete medical history as it pertains to your nerve injury, a lawyer could steer you in the right direction, as well as clarify the specific malpractice laws and statutes in your state.
This link could be of some help, as this person was in a similar situation. Though you did not undergo hip replacement surgery, this individual also suffered a damaged peroneal nerve: (removed)