Pivot points have all moved to center / centre

I've just fired up my endless runner to do some more animation only to discover that all the pivot points have moved. They were at the elbow, shoulder, knee etc now they've all moved to the centre of the body part. How can I move them back to where they were (or very close) without losing my animation?

I've reopened the sprite sheet and all the pivot points are where they should be. I've clicked on 'Apply' but it's made no difference.

Now I've deleted and reimported, re sliced and repositioned all the pivot points and once I place them in the hierarchy all the pivot points have moved to the centre. What am I doing wrong?

 

Where are you seeing the pivots centered, in the scene view?

Have you tried toggling this button:

 

Thanks