Radiological evaluation of patellofemoral instability and possible causes of assessment errors.

Patellofemoral instability (PI) is the disruption of the patella's relationship with the trochlear groove as a result of abnormal movement of the patella. To identify the presence of PI, conventional radiographs (anteroposterior, lateral, and axial or skyline views), magnetic resonance imaging, and computed tomography are used. In this study, we examined four main instability factors: Trochlear dysplasia, patella alta, tibial tuberosity-trochlear groove distance, and patellar tilt.

The relationship between patellar volume and trochlear volume in patients with patellofemoral instability.

Aim: To investigate a possible relationship between both the volume and morphology of the patella and the volume of the trochlea in trochlear dysplasia (TD).

Materials And Methods: Eighteen patients with TD and 18 controls were evaluated retrospectively in two groups using computed tomography (CT). Patellar morphology was evaluated with the standard measurement methods described in the literature.