Patellar instability: current approach.

Abstract

Patellar dislocations present predominantly during adolescence, with a higher incidence observed among female patients. Patellofemoral joint stability depends critically on both osseous anatomy and soft tissue structures. Patellofemoral pathology can be classified into three major groups: objective patellar instability OPI, potential patellar instability and painful patellar syndrome. Three primary risk factors predispose individuals to patellar dislocation: trochlear dysplasia, patella alta and increased tibial tuberosity-trochlear groove (TT-TG) distance. Three secondary risk factors should be considered: femoral and tibial rotational abnormalities and valgus deformity. MRI has become the imaging modality of choice, enabling precise quantification of OPI risk factors in a single imaging examination. The 'menu à la carte' approach guides the treatment of OPI by addressing the most relevant anatomical risk factors for each patient using statistical thresholds.