Nice to meet you although I wish it were under better circumstances. Wow, the numbness and all sure does sound miserable. I'm so sorry you're suffering. I didn't know what Avascular necrosis was so I looked it up and did some reading about it. I was not able to find anything relating skin problems like yours to the disease. Now, I'm not a doc nor in the medical field and your doctor is most likely correct in that it comes with the bone problems. You might want to see a dermatologist to get some additional input.
Keep in touch,
Moderator ~ Fibromyalgia and Chronic Pain forums
Fibromyalgia, IDDM. UC, , Osteoarthritis and others trying to mess up life.
The microwave oven is the consolation prize in our struggle to understand physics. ~Jason Love