It is a condition that occurs when there is less of blood supply to the bone. Because bone is living tissue that requires blood, and interruption to the blood supply causes the bone to die. If left untreated this process eventually causes the bone to collapse. It Occurs mostly in hip point.
In early stage-no symptoms
As disease progress- Increased joint pain as bone and joint began to collapse
Limited range of Motion due to pain
Trauma, Steroid use, Excessive alcohol use, Certain medical treatments