Hello everybody,

I'm modelling the ligaments of the knee joint using the hyper elastic anisotropic model (The Holzapfel one), but I'm getting compressive stress in the ligaments. Therefore the four ligaments are transferring loads from the femur to the tibia which is not correct

 I know that for an elastic material, I just have to tick the box "Avoid compression" when defining the material, but it isn't possible to do so with a Hyper elastic material. Does anyone know how to model a ligament that can only take tensile loads?

Thanks,

Alex Riveaux

Anglia Ruskin University