The invention relates to a system (100) for propagating a model mesh based on a first mean model mesh and on a second mean model mesh, the system comprising: a registration unit (110) for computing a registration transformation for registering the first model mesh with the first mean model mesh a forward transformation unit (120) for transforming the model mesh into a registered model mesh using the registration transformation a computation unit (130) for computing a propagation field for propagating the registered model mesh, the propagation field comprising vectors of displacements of vertices of the second mean model mesh relative to respective vertices of the first mean model mesh a propagation unit (140) for transforming the registered model mesh into the propagated registered model mesh based on applying the vertex displacement vectors comprised in the propagation field to respective vertices of the registered model mesh and an inverse transformation unit (150) for transforming the propagated registered model mesh into the propagated model mesh using the inverse of the registration transformation, thereby propagating the model mesh. Using the propagation field comprising vectors of displacements of vertices of the second mean model mesh relative to respective vertices of the first mean model mesh improves modeling motion of anatomical shapes. Advantageously, the propagation field of vertex displacement vectors is straightforward to compute and to apply.
