[vhfpmr (OP)]

I injured my hand in a fall about 10 days ago, and the bruise (which isn't even at the point of impact) has disappeared and reappeared several times, more than once in the same day sometimes.

[evan_au]

It is normal for a bruise to move and change color over a few days, but appearing and reappearing several times on the same day sounds a little extreme!

Is it possible that blood leaked out under your skin as a result of the injury? It may pool some distance from the actual site of the injury.
And it could move, depending on what you have been doing: lying down, walking, etc (if you have very loose skin).
Changes in lighting (or clothing) could affect the visibility of the bruise.

[vhfpmr (OP)]

The site of the impact was on the palm side, near where the muscly pad at the base of the thumb joins the wrist, there was no bruise there, the bruise is on the back of my hand in the soft depression in the cleft between the thumb and forefinger. It seems to reappear each time I do something that hurts, then fades again over a few hours. It's very odd, I've never had a bruise that doesn't just appear and then fade away.

[Colin2B]

It's not unusual for a bruise to be at a different location to the impact especially when it's like the injury you describe. The impact might have ruptured a small vein or capillaries in the back of the hand by crushing it against a bone. it is possible that movement is disturbing the clot which leaks blood. If it still hurts with movement there is obviously still some soft tissue injury.
Might be worth having it checked to see whether you have cracked the bone.

[vhfpmr (OP)]

Might be worth having it checked to see whether you have cracked the bone.

The reason for my curiosity is that I wondered whether the reason for the reappearing bruise might be a fracture that's getting disturbed each time I do something that hurts. When I told the doctor about it last week I just got the sort of silence you get when people think you're lying/talking nonsense, which is why I wondered how unusual it is.