Joint Replacement failing to adhere the Hip Prosthetic to the femur bone

I have had CIDP the last 15 years. I am mobile. I had a Total Hip Replacement February 2018. A year later, due to pain issues in quad muscles and my hip, the x-rays show that the femoral stem never attached to the bone, therefore my leg is not stable. I need an extensive revision surgery which will replace the stem with a longer one. The ball and joint are stable. My concern is what will stop this revision from failing? I have learned my anti-inflammatory IVIG treatments can cause this. Has anyone else experienced joint replacement problems?