Magnetic resonance imaging of degenerative changes of the posterior cruciate ligament

Abstract

Background Mucoid degeneration and ganglia reflect a continuum of degenerative changes within the posterior cruciate ligament (PCL). Purpose To assess the prevalence of and radiologists' familiarity with PCL mucoid degeneration and ganglia. Material and Methods Knee magnetic resonance imaging (MRI) from July 2013 to June 2015, excluding patients who had a preceding trauma or MRI findings indicative of a prior injury, were retrospectively reviewed, with the specific request to assess degenerative changes of the PCL, by the same musculoskeletal radiologists who previously reported these examinations, and one fellow. Results A total of 692 patients entered this study. The radiologists and the fellow together identified mucoid degeneration in 34 patients (4.9%), ganglia in 14 patients (2.0%), and both in four patients (0.6%). Several patterns of PCL mucoid degeneration were identified: diffuse thickening in seven patients, partial thickening in 16 (four associated with a ganglion), longitudinal intraligamentous PCL signal-intensity abnormalities resembling a "tram track" in 15. In all cases there was increased signal intensity on fluid-sensitive sequences. In the previous reports, only three cases of PCL mucoid degeneration out of 38 (7.9%) were described, with intraligamentous PCL signal-intensity abnormalities. In the reports of the patients with degeneration and ganglia, only ganglia were described. In the previous reports, ganglia were correctly diagnosed. Conclusion Mucoid degeneration of the PCL is much more common than previously assumed and is underestimated by radiologists.

Quantitative mapping of acute and chronic PCL pathology with 3 T MRI: a prospectively enrolled patient cohort

“…The clinical diagnosis of a PCL injury can be challenging with conventional magnetic resonance (MR) imaging for diagnosing both acute and chronic PCL injuries (DePhillipo et al, 2018; Orakzai et al, 2010; Servant et al, 2004; Tewes et al, 1997). When a PCL tear is suspected, radiologists will commonly examine the patient’s MR images for secondary signs such as PCL thickening, increased signal or elongation (Cho et al, 2001; Draghi et al, 2017; Geeslin et al, 2017; Rodriguez et al, 2008). However, several authors have reported that the appearance of the PCL on conventional MR imaging is not reliable in predicting its functional integrity or degenerative changes (Akisue, Kurosaka, Yoshiya, Kuroda, and Mizuno, 2011; McMonagle et al, 2013; Orakzai et al, 2010; Rodriguez et al, 2008).…”

The Evaluation of Degeneration of Posterior Cruciate Ligament Using CT Hounsfield Unit in Knee Osteoarthritis

“…Considering the fact that MRI is not useful enough to analyze the quality within the ligaments which have a short echo time [2], the measurement of CT HU value could be a valid method to provide us more details about the ligament property. Although further studies are required, the evaluation using the CT HU value could be applied not only for PCL but also for other soft tissues.…”

“…However, MRI is only useful to detect rupture, mucoid degeneration and ganglion in PCLs and it is not enough to analyze the quality within the ligaments which have a short echo time [2]. On the other hand, computed tomography (CT) scan is also one of the conventional modalities to assess knee OA.…”

The evaluation of degeneration of posterior cruciate ligament using CT Hounsfield unit in knee osteoarthritis

“…Magnetic resonance imaging (MRI) has been commonly used to evaluate PCL degeneration. However, MRI is only useful for detecting rupture, mucoid degeneration, and ganglion in PCLs; it is not sensitive enough to analyze the quality within the ligaments that have a short echo time [2]. Conversely, computed tomography (CT) is a conventional modality used to assess knee OA.…”