Comparison of patellar deviation and sulcus angle between healthy subjects and patellofemoral pain syndrome patients using MRI

It has been reported that patella lateralization and trochlear dysplasia are the most important malalignment factors related to patellofemoral joint (PFJ) that may lead to high compression force on lateral side of knee and finally damaging this joint. The aim of this study was the comparison of the patella deviation and sulcus angle between two groups of healthy and patellofemoral pain syndrome (PFPS) patients by using noninvasive and precise methods of MRI.
21 subjects were classified into two groups of healthy and patient. Patella deviation and sulcus angle were measured in 40 degrees flexion of knee using MRI.
Patella lateralization in PFPS group is significantly higher than healthy one (p=0.04) while there was no significant difference in the sulcus angle.
Findings showed that the cause of pain due to patella lateralization could not be related to shallowing the trochlear groove but delaying or weakness of vastus medialis oblique (VMO) could be a risk factor for inappropriate displacement of patella.