Investigation of the relationship between patellofemoral joint morphology parameters and chondromalacia and osteoarthritis, and their impact on disease progression

The patellofemoral joint (PFJ) is a structure that forms the anterior part of the knee and plays a significant role in load transfer during movement. Morphological abnormalities in this joint can lead to uneven load distribution and cartilage damage. The aim of this study is to evaluate the relationship between various quantitative parameters of PFJ morphology and patellofemoral osteoarthritis (PFOA) and patellar chondromalacia (CM) using magnetic resonance imaging (MRI), and to investigate the effects of these morphological features on disease severity and progression. For this purpose, the study included 305 MRI scans from 232 patients who underwent at least two knee MRI scans at different times between 2010 and 2024. PFJ morphology was assessed through measurements of Wiberg type, patellar transverse diameter, sulcus angle, lateral patellar tilt angle, lateral and medial trochlear inclination angles, trochlear depth, Insall – Salvati index (ISI), and patellofemoral index (PFI). Findings of PFOA and patellar CM were graded using MRI-based Kellgren – Lawrence and Modified Outerbridge classifications. The collected data were analyzed to determine the relationships between morphological parameters and disease severity and progression. Analyses revealed that ISI and PFI were significantly associated with both PFOA and CM severity, while trochlear depth was significantly associated only with PFOA progression. Wiberg type I morphology was found to have a protective effect against patellar CM and CM progression. Age was also shown to have a significant effect on disease severity and progression. The findings suggest that PFJ morphology may play a key role in patellar cartilage health, and the longitudinal design of the study allowed for the evaluation of changes and disease progression over time. In conclusion, the results indicate that morphological parameters measurable via MRI can be used as early diagnostic markers for PFOA and patellar CM and may assist in identifying high-risk individuals.