Jung Eun Lee, Presenter: Nothing to Disclose

Ji Seon Park MD, PhD, Abstract Co-Author: Nothing to Disclose

Myung-Won You, Abstract Co-Author: Nothing to Disclose

So Young Park, Abstract Co-Author: Nothing to Disclose

Wook Jin, Abstract Co-Author: Nothing to Disclose

Kyung Nam Ryu MD, PhD, Abstract Co-Author: Nothing to Disclose

Seong Jin Park MD, PhD, Abstract Co-Author: Nothing to Disclose

Eui Jong Kim, Abstract Co-Author: Nothing to Disclose

To evaluate the magnetic resonance imaging (MRI) features of chronic injury of posterior cruciate ligament(PCL) and to consider its clinical significance (PCL injury, particularly in chronic cases, has known to show normal appearance on MRI, however, there is no detailed MR description about chronic PCL injury.)

From september 2002 to november 2010, 45 knee MR studies at least 3months after knee trauma obstained in 45 patients(male: female= 40:5; mean age 31.6, range 15~65), underwent arthroscopic PCL reconstruction were reviewed retrospectively by two radiologists. PCL signal characteristics, contour(irregular or wavy), continuity and thickness were assessed by using sagittal proton density weighted(PDW) and T2-weighted(T2W) images. And presence of increased signal intensity(SI) and contour change were evaluated on PDW axial scans, additionally. Based on overall MR findings, each PCL was classified as tear, degeneration, and normal.

Increased SI with or without fluid SI on PDW and T2W sagittal images and contour deformity either on sagittal or axial PDW image were observed in 28/45(62%), suggested partial tear. Mild SI or contour change on PDW/T2W sagittal scan and mild signal change without contour deformity on axial PDW image were classified into degeneration(11/45, 24%). Normal SI, minimal contour change and preserved continuity were diagnosed as normal(2/45,4%). Discontinuity or nonvisible ligament were seen in 4/45(8%), diagnosed as complete tear. Majority of PCL showed contour deformity(irregular or wavy,37/45,82%), wavy contour was seen in 14/45(31%). The mean thickness of midportion and proximal portion were 4.6mm and 5.5mm respectively, with a difference of 9mm.

About one third cases of chronic PCL injury revealed normal appearance or only degenerative change on MR exam. The MR findings of chronic PCL injury can be ambiguous and therefore clinical correlation must be considered

Chronic PCL injury cannot be diagnosed by MRI only, and clinical correlation including stress test must be considered

Lee, J, Park, J, You, M, Park, S, Jin, W, Ryu, K, Park, S, Kim, E, MRI Findings of Chronic Injury of Posterior Cruciate Ligament.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12035568.html