“Limp following back surgery?”

Hi...I had a spinal cord stimulator fitted in Dec 2019 under a GA. When I came round I noticed that my right leg and foot were very numb (similar to when one sleeps on one's arm). I suffered terrible pain from the lower back, through my buttock, and into my leg in the weeks following the op and was told that my sciatic nerve was crushed at S1 level whilst under the GA. I am still walking with a limp and altered gait and I still cannot push myself up onto the ball of my right foot. My heel drops down when descending stairs. I still have muscle wastage in my calf, back of thigh, and right buttock (glute). This leg was always the stronger of the leg but not any longer. Is there anything that can be done surgically or otherwise to regenerate the damaged nerves that serve these muscles? This problem is getting me down.