Jung-Eun Cheon MD, Presenter: Nothing to Disclose

Won Joon Yoo, Abstract Co-Author: Nothing to Disclose

In-One Kim, Abstract Co-Author: Nothing to Disclose

Woo Sun Kim MD, Abstract Co-Author: Nothing to Disclose

Young-Hun Choi, Abstract Co-Author: Nothing to Disclose

Kyung Mo Yeon MD, Abstract Co-Author: Nothing to Disclose

To determine the relevance of meniscal deformation and displacement in MR imaging to tears using arthroscopic findings as a standard of reference in children with discoid lateral meniscus (DLM).

MR imaging and intraoperative videos of 69 consecutive patients (79 knees), treated arthroscopically for suspicious DLM tears, were reviewed. Mean age at surgery was 10.9 years (range, 4.3-17.6). Signal changes and morphologic changes (deformation or displacement) of DLM in MR images were graded by two independent observers using authors’ modifications of previously described classification schemes, and then the grades were determined by consensus of the observers. Meniscal tears were assessed by an observer, blinded to the MR imaging, based on arthroscopic findings. Signal changes and morphologic changes of DLM in MR images were correlated with tears. Fisher's exact test was used to determine the significances of correlations. P-values < 0.05 were considered significant.

Tears were found more frequently in menisci showing morphologic changes in MR images (p=0.00124). Of the 25 menisci with a grade 3 signal change (linear or band-like signal intensity extending to the superior or inferior meniscal surface), 24 had tears and a horizontal cleavage was the most commonly associated tear type. Of the 50 menisci with a grade 1 (dot-like intrameniscal signal change), a grade 2 (linear or band-like intrameniscal signal change) or a diffuse signal change, 34 menisci were morphologically changed in MR images and 29 of these (85%) were torn, while 9 of 16 menisci (56%) not morphologically changed were torn (p=0.0363).

Meniscal deformation or displacement observed in preoperative MR imaging was correlated with meniscal tears with a higher risk. These MR imaging findings may be helpful for predicting tears especially when the DLM shows a signal intensity other than a grade 3 change.

Meniscal deformation or displacement observed in preoperative MR imaging can be helpful for predicting tear especially when discoid lateral meniscus shows indetermined intrameniscal signal abnormality

Cheon, J, Yoo, W, Kim, I, Kim, W, Choi, Y, Yeon, K, Meniscal Deformation and Displacement in Children with Discoid Lateral Meniscus: An MR Imaging Study.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11013757.html