Extra Joints Elbow problem

GhostInTheShell

Hi Guys, my problem is, i tryed to place the extra joints in the elbow and knee and i can't make it work very well, i did some skinning and can't make it look a good deformation, so if someone could help me to make this setup without using blendshapes, i will be very grateful

(ps> i'm using maya)

 -Ghost