I have stage 3 kienbock disease , how long does it take to progress to stage 4 ?

Not Sure: Keinbocks disease is occurs for unknown reasons. It's severity is graded 1-4, but not everyone goes through all 4 phases. Sometimes it gets better on it's own or with some surgery. Stage 3 has a and b types with b being worse. Stage 4 is complete collapse of the lunate with associated wrist arthritis. You usually need some type of surgery to make this better. Get checked out by a hand surgeon.