What is the alternative medicine for osteonecrosis?

Nothing i'm aware of. Osteonecrosis is a poorly understood process. It can be caused by steroids, trauma, vascular insult, alcohol, or be idiopathic. Once it has started, I am not aware of any medications or alternative medicines which arrest the process. There has been some suggestion that bisphosphonates can arrest the process in the case of idiopathic osteonecrosis (perthes), but this is still investigational.
Is there one?? Osteonecrosis means bone death. This is a hard thing to treat. Sometime the bone resorbs. Othertimes it might need to be surgically repaired. I am not aware of any alternative medicine that could help.
Yes, special cases. In idiopathic osteonecrosis, Ficat stage I or II, familial and acquired thrombophilia (Factor V Leiden, Prothrombin gene mutations, high Factors VIII, XI, high homocysteine, lupus anticoagulant) can cause osteonecrosis, and the progression of the disease can often be halted by anticoagulant therapy, provided there are no contraindications to osteonecrosis.