MR evaluation of mediopatellar plica.
OBJECTIVE
Evaluation of the usefulness of MR imaging for diagnosing mediopatellar plica (MP) of the knee joint.


METHODS
We prospectively examined MR images of 40 knee joints in 30 patients with symptoms. The pulse sequences were SE T1-weighted images (600/26 ms), T2-weighted images (1800/70), and FLASH images (320/15/flip angle 90 degrees). When a low-intensity band was found above the medial condyle of the femur on T1-weighted and T2-weighted MR images, we defined it as MP. We compared these MR findings with arthroscopic findings, including the SAKAKIBARA classification of MP.


RESULTS
In 29 of the 40 knee joints in which MP was arthroscopically found, 27 were correctly diagnosed as having MP on MR. In the remaining 11 without MP, 9 were correctly diagnosed by MR.


CONCLUSIONS
MR images are useful not only for detecting MP but also for evaluating its extension. Our results suggest that MR imaging is useful as a screening method for detecting MP before arthroscopy.
Nakanishi
K
K
Department of Radiology, Osaka University Medical School, Japan.
Inoue
M
M
Ishida
T
T
Murakami
T
T
Tsuda
K
K
Ikezoe
J
J
Nakamura
H
H
D000293:Adolescent; D000328:Adult; D002648:Child; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000002:abnormalities* / Q000000981:diagnostic imaging / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D011859:Radiography