Like Bednobs, I had my knee operated on - in April last year. The scar was starting to go white after 11 months (from the bottom up) when I had to have it operated on again. Back to square one. The scar from the original injury, 25 years ago, has been white for ages.
Years ago, I was sunbathing on a beach in Spain, and there was a girl there who had had open heart surgery. She didn't seem at all bothered about wearing a bikini and letting everyone see the scar. The only problem is that a suntan makes the scar look whiter as that bit doesn't tan.