Theoretical use of 3D CT to predict method of patella realignment.

Procedures for the treatment of patello-femoral malalignment are grouped into two categories, proximal realignment and distal realignment. However, no clear indications in respect of these realignments have been reported. We have tried to evaluate patello-femoral alignment three-dimensionally using CT. The results lead us to group patients with recurrent patella dislocation into three types. Type 1 comprises patients with normal patello-femoral alignment. Type 2 comprises patients whose patella only deviates laterally and who need proximal realignment. Type 3 comprises patients whose patella and tibial tuberosity both deviate laterally and who need both proximal and distal realignment.