Robert Michael Kwee, Presenter: Nothing to Disclose

Bashir Zikria, Abstract Co-Author: Nothing to Disclose

John A. Carrino MD, MPH, Abstract Co-Author: Consultant, BioClinica, Inc Consultant, Pfizer Inc Advisory Board, General Electric Company

Shadpour Demehri MD, Abstract Co-Author: Nothing to Disclose

To assess the prevalence of mucoid degeneration of the anterior cruciate ligament (ACL) and its association with cartilage and meniscal abnormalities using magnetic resonance imaging (MRI) of the knee.

Institutional review board approval was obtained and patient consent was waived for this HIPAA-compliant, retrospective study. Four hundred and seventy-one consecutive knee MRI examinations were identified. Fifty-three consecutive knee MRIs with mucoid degeneration of the ACL (M/F=0.71; median age of 53.6 years, range 26-81) were identified and matched with age and sex to 106 consecutive control knee MRIs without mucoid degeneration or tear of the ACL using frequency matching (case-control ratio of 1:2). Abnormalities of the cartilage of the medial (MTC) and lateral (LTC) tibiofemoral compartments and menisci were semiquantitatively assessed by using the Whole-Organ MR Imaging Score (WORMS) system. Differences in cartilage and meniscal abnormalities between patients with mucoid ACL degeneration and controls were assessed by performing chi-square and Mann–Whitney U tests.

Prevalence of mucoid degeneration of the ACL was 12.8%. Patients with mucoid ACL degeneration were older than all other patients (mean age of 53.6 vs. 43.7 years, P<0.001) but there was no gender predilection (P=0.319). The frequency of severe cartilage damage (WORMS ≥5) in the MTC was significantly higher in knees with mucoid ACL degeneration than in the control group (49.1% vs. 18.9%, P<0.001), but there was no significant difference in the LTC (13.2% vs. 8.5% P=0.351). Knees with mucoid ACL degeneration had significantly more meniscal damage compared to controls (mean WORMS of medial meniscus of 2.7 vs. 2.1, P=0.033; and mean WORMS of lateral meniscus of 1.1 vs 0.6, P=0.012).

Prevalence of mucoid degeneration of the ACL in patients referred for knee MR imaging is 12.8%. The presence of mucoid degeneration of the ACL is strongly associated with severe MTC osteoarthritis (OA) as well as more meniscal damage.

Given the known association between ACL insufficiency and development of MTC OA, our results suggest that patients with mucoid ACL degeneration should also be carefully examined for ACL instability.

Kwee, R, Zikria, B, Carrino, J, Demehri, S, Mucoid Degeneration of the Anterior Cruciate Ligament: Prevalence and Association with Cartilage and Meniscal Integrity at MR Imaging.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14011035.html