The plica syndrome: diagnostic value of MRI with arthroscopic correlation.

Purpose: Our goal was to evaluate the diagnostic value of MRI in plica syndrome.
Method: MR images of a patient group (n = 55) with arthroscopically confirmed pathologic mediopatellar plicae were retrospectively analyzed and compared with those of a control group (n = 100). We obtained axial multiplanar gradient-recalled (MPGR), axial T1-weighted, and sagittal T2-weighted MR images. MR images were assessed for the width and length of all medial plicae.
Results: In the diagnosis of plica syndrome, sensitivity and specificity were 73 and 78% on axial MPGR images, 71 and 83% on sagittal T2-weighted images, and 95 and 72% on combination of both images, respectively. The incidence of pathologic medial plica increased with a criterion of extension beyond the medial end of the patella on axial MPGR images.
Conclusion: MRI is a useful screening method in the diagnosis of plica syndrome.