Avascular necrosis happens when the blood supply to the ball of the hip joint drops, and the bone slowly starts to weaken. The tricky part is that the earliest stages often look silent on the outside. Pain is mild, mobility feels normal, and most people assume it is just a muscle issue. This is why stage 1 and stage 2 are such important phases. The bone is still structurally intact, so medicines, lifestyle changes, and targeted therapies can slow the disease and sometimes delay the need for surg