Objectives: Patellofemoral instability (PFI) occurs predominantly during adolescence, with a higher incidence in females compared to males. Anatomical risk factors such as trochlear dysplasia, patellar height abnormalities, lateralized patella, and patellar tilt play a key role in the pathogenesis of PFI. However, little is currently known about how these parameters change during growth or differ between sexes. The aim of this study was to investigate whether these risk factors behave differently between sexes with increasing knee size. Methods: We retrospectively analyzed 315 knee magnetic resonance imaging (MRI) scans, including 169 female and 146 male participants. We performed quantitative morphometric measurements of the patellofemoral joint using standardized MRI-based techniques. The evaluated morphological risk factors included indices of trochlear dysplasia (trochlear depth, sulcus angle, and lateral trochlear inclination angle), patellar height (Caton–Deschamps Index and patellotrochlear index), patellar lateralization (tibial tubercle–trochlear groove TT–TG distance and tibial tubercle–posterior cruciate ligament TT–PCL distance), and patellar tilt (lateral patellar inclination angle, Fulkerson angle, and Laurin angle). We used independent sample t-tests to compare morphometric parameters between sexes and performed linear regression analyses to examine the associations between these parameters and overall knee size. Results: Linear regression analyses revealed sex-specific differences in nearly all evaluated parameters relative to individual knee size. Significant differences between females and males were found in femoral width, TT–PCL distance, and patellotrochlear index (p < 0.05). Conclusion: The findings demonstrate that anatomical risk factors for patellofemoral instability develop differently between females and males as femoral width increases. This highlights the importance of individualized assessment of risk factors across different stages of growth. Understanding these sex-specific developmental variations may contribute to more personalized patient evaluation and improve clinical decision-making in the management of patellofemoral instability.
Schroedter et al. (Wed,) studied this question.