Avascular necrosis in hip joint. Done.

My doctor explained about AVN that blood supply to hip-joint bone gets reduced, thus causing bone-death. Then he gave medicines for 8 months with regular follow-up. Then on 8 months, he asked that we can check as if blood supply has become good or not by doing nerve conduction study. My nerve conduction study(nerves studied: common peroneal, posterior tibial; sensory: sureal) is showing everything normal, thus he deduced that my blood-supply has become good. But other doctor said, that nerve conduction study is not required in this case. Also when i did MRI of hip joint, it has gone worse. Any thoughts please... NCV & EMG Findings: 1. Motor conduction study showed normal distal latencies from posterior tibial nerves & common peroneal nerves. CMAP was normal. CV was marginally reduced. 2. F waves were normal 3. Sensory nerve conduction study showed normal peak SNAP latencies from sural nerves with preserved SNAP amplitudes. CV was normal. 4. Needle EMG not done.