Patellofemoral joint is an under reported joint in MRI knee – A retrospective, cross-sectional study

Background Patellofemoral joint (PFJ) pathology accounts for upto 40% of cases of knee pain. It has been suggested that PFJ pathology may be underreported in Magnetic Resonance Imaging (MRI) Knee reports. The objective of this study was to elucidate whether PFJ was reported in MRI knee reports at our institution. Materials and methods A retrospective review of 103 consecutive Knee MRIs over a 2-month period was performed by an author, blinded to the reports, at our institution. We analysed whether PFJ was mentioned in MRI knee reports and whether any significant PFJ pathology was present in the scans of this cohort. Images were also reviewed for any underlying causes of PFJ pathology such as trochlear dysplasia (TD) that can result in patellar instability or maltracking. Results PFJ was not mentioned in 79/103 cases (77%). 24 cases had trochlear dysplasia. There was no association between PFJ reporting and trochlear dysplasia (p value = 0.50). Conclusion PFJ is not mentioned in the majority of Knee MRI reports. PFJ pathology is an important cause of anterior knee and should be reported.