Diagnostic value of postoperative magnetic resonance imaging in predicting clinical outcomes after meniscal repair: A retrospective cohort study.

backgroundMagnetic resonance imaging (MRI) is widely used to evaluate meniscal healing after surgical repair; however, the extent to which postoperative MRI findings reflect clinically meaningful recovery remains uncertain. This study aimed to examine the relationship between MRI-based healing appearance and patient-reported functional outcomes after meniscal repair.

methodsThis retrospective observational study included adult patients who underwent arthroscopic meniscal repair between January 2018 and December 2024 at a tertiary care centre. Patients with at least 12 months of follow-up, available postoperative MRI, and complete clinical outcome data were included. Postoperative MRI was obtained at a mean of 18.6 ± 7.4 months after surgery (range: 12-36 months). Meniscal healing on MRI was classified as complete healing, partial healing, or failed healing/retear. Clinical outcomes were assessed using the International Knee Documentation Committee (IKDC), Lysholm, and Tegner scores. Clinical success was defined as IKDC ≥ 80 and Lysholm ≥ 85. The association between MRI healing status and clinical outcomes was evaluated using group comparisons and correlation analyses.

resultsA total of 240 patients (mean age 27.4 ± 6.8 years; 71.7% male) were analyzed. MRI demonstrated complete healing in 40.8% of patients, partial healing in 31.7%, and failed healing or retear in 27.5%. Mean IKDC, Lysholm, and Tegner scores differed significantly across MRI groups (all p ≤ 0.002), with lower scores observed in patients with MRI-defined failure. However, 63.6% of patients classified as having failed healing on MRI met the criteria for clinical success. MRI healing status showed moderate correlations with IKDC (r = 0.42), Lysholm (r = 0.39), and Tegner (r = 0.31) scores (all p < 0.001). The MRI-IKDC correlation was higher in patients who underwent concomitant anterior cruciate ligament reconstruction than in those who underwent isolated meniscal repair.

conclusionsPostoperative MRI appearance after meniscal repair is associated with patient-reported and functional outcomes, but the strength of this relationship is limited. MRI-defined structural abnormalities may persist despite satisfactory clinical recovery, indicating that MRI has restricted specificity for identifying clinically meaningful failure. These findings suggest that MRI should be interpreted in conjunction with clinical assessment rather than used as a standalone indicator of postoperative success.