Had Laminectomy L4L5 Went Well All Pain And Associated Problems

had laminectomy L4L5 went well all pain and associated problems gone . did lots of walking as told to. after 4 weeks woke up with sharp pain left inner buttock and top hamstring area only when I lay down and move left leg or twist extensively to my left side while in sitting position . no pain when I sit ,walk bend lift . if I lay on my back pain is bad when I lift left leg while leg straight. had contrast MRI post operation and was told all ok ??? do you have any ideas . taking nerve pain med and helps but pain upper hamstring area still there but duller .