Can't reset to rest pose

Hi,
I’m having an issue : I try to reset a current pose to the rest pose.
So i delete all the keyframes, hit W > Clear User Transforms, and it reset all the pose, but the result is not exactly like the rest pose :



Actual pose on the left, rest pose on the right.

I also tried Alt + R/G/S, copy the rest pose and paste it in actual pose, … Still this shitf on these bones.
Thanks for any help.

It’s tough to tell without the blend file. If those two bones are using stretch_to constraints they need to be reset. If the armature is edited to change the length of a stretch_to bone the constraint needs to have its reset button clicked.

The two green bones are bendy bones with stretch to modifier. I hit the rest button of eatch modifier and it solved the problem.
Thanks for your complete answer.