Your question is not very clear. Did he undergo surgery for neck of femur fracture? Or for sciatic nerve palsy?
The symptoms you are describing right now are related to sciatic nerve.
The nerve maybe healing or it is still damaged. If the symptoms keep improving, then the nerve is healing. In that case, just wait. If the symptoms do not improve, get an EMG-NCV test 3 weeks after the surgery.
Next Steps
As of now, you may give him Tab Gabaneuron (300mg)...once a day at 7pm for 10 days. He may experience some sleepiness for the first couple of days but that will subside after the first couple of days.
Do get back after 1 week to reassess if the tablet has worked or if we need to increase the dose.