Faced with excruciating pain brought on by avascular necrosis (AVN), Mishcah Hamilton has found herself in a race against permanent immobility, requiring emergency hip-replacement surgery after suffering a total joint collapse because of sickle cell disease. A common but devastating complication of the disease, AVN is the death of bone tissue due to a loss of blood supply, causing the bone to weaken and potentially collapse, most commonly affecting the hip, knee, shoulder, or ankle. Read more