Meniscal vascular contact loss ratio (MVCLR): A novel MRI index for predicting meniscal irreparability.

BACKGROUND

Accurate preoperative identification of meniscal tears with limited healing potential remains challenging. Conventional magnetic resonance imaging (MRI) descriptors - tear pattern, extrusion, displacement, and signal alterations - offer limited insight into the biological viability of the vascular peripheral rim. No MRI-based parameter currently quantifies the loss of meniscocapsular contact, the anatomical region most critical for vascular-mediated healing. This gap limits the ability to anticipate reparability and contributes to intraoperative decision variability.

PURPOSE: To validate the meniscal vascular contact loss ratio (MVCLR), a novel geometric MRI metric, as a predictor of meniscal irreparability.

METHODS

A retrospective cohort of 138 patients undergoing arthroscopic surgery for symptomatic meniscal tears was analyzed. MVCLR was calculated as the proportion of the vascularizable meniscal perimeter lacking capsular contact on proton-density fat-suppressed MRI. Intra- and interobserver reliability were assessed using intraclass correlation coefficients (ICCs). Diagnostic performance for predicting arthroscopically confirmed irreparability was evaluated using receiver operating characteristic (ROC) analysis, Youden-optimized cutoff determination, and multivariable logistic regression.

RESULTS

Mean MVCLR was significantly higher in irreparable tears compared with repairable tears (54.8 % ± 12.6 % vs 27.9 % ± 10.3 %, P < 0.001). MVCLR demonstrated excellent discriminative ability (area under the curve 0.88; 95 % confidence interval (CI), 0.82-0.93). A cutoff of 47 % yielded 82 % sensitivity and 85 % specificity. Each 10 % increase in MVCLR independently increased the odds of irreparability by 2.3-fold (95 % CI, 1.7-3.2). Reliability was high, with ICCs of 0.87 (interobserver) and 0.92 (intraobserver).

CONCLUSION

MVCLR reliably predicted meniscal irreparability by quantifying peripheral contact loss and demonstrated excellent diagnostic accuracy. Its primary limitation is that intraoperative determination of irreparability remains partially subjective despite predefined criteria.