[Patella instability].

In respect to the risk of recurrent patella instability, new biomechanical factors have been ruled out, and among these trochlear dysplasia is the most important single factor. The algorithm for operative intervention should be based upon X-rays and MRI scans. Medial implication is considered obsolete and distal realignment as well as lateral release procedures should be minimized, based upon deteriorating results. Reconstruction of medial structures becomes increasingly frequent, based upon good results, however, in cases of higher degree of trochlear dysplasia, trochleoplasty should be considered.