A reference jig comprises a base adapted to be secured to a distal end of a bone. An adjustment mechanism has a bracket, one or more rotational joints operatively mounting the bracket to the base, whereby the bracket is rotatable in two or more rotational degrees of freedom relative to the base, and one or more translational joints. A landmark alignment unit is operatively connectable to the bracket by the at least one translational joint, the landmark alignment unit having a bone alignment component configured to be aligned with at least one bone landmark.