Problem when stretching the leg

[Anonymous]

Hi ! I've got some problem with my IK leg, the ik itself work just fine but when I stretch it (with some nodes in the node editor), the mesh deforms. I deleted the history of the mesh, freezed the attributes and also lock them, I even recreate the joints from the start and reorient them in different ways, but the mesh keep deforming when I stretch it. Can someone know how can I solve this problem ? 

Thanks in advance.

Ps: I attached the deforming leg and the node of my Ik setup in the node editor.