Chronic anterior cruciate ligament tears and associated meniscal and traumatic cartilage lesions: evaluation with morphological sequences at 3.0 T

To investigate the diagnostic efficacy of morphological sequences at 3.0 T MR imaging in detecting anterior cruciate ligament (ACL), meniscal pathology and traumatic cartilage legions in young patients with chronic deficient anterior cruciate ligament knees.

This prospective study included 43 patients (39 male) between the age of 15 and 37 years (mean age 22.6 years) with a history of knee injury sustained at least 3 months prior to the decision to repair a torn ACL. All patients underwent a 3.0 T MR scan with the same standard protocol, including intermediate-weighted and three-dimensional spoiled gradient-recalled T1-weighted sequences with fat saturation and subsequently surgical reconstruction of the ACL, along with meniscal and cartilage repair, when necessary.

All ACL tears were correctly interpreted by 3.0 T MR images. The sensitivity of the MR scans regarding tears of the medial meniscus was 93.7%, the specificity 92.6%, the positive predictive value 88.2% and the negative predictive value 95.8%. The sensitivity of the MR scans regarding tears of lateral meniscus was 85.7%, the specificity was 93.1%, the positive predictive value 85.7% and the negative predictive value 93.1%. With regard to the grading of the cartilage lesions, Cohen’s kappa coefficient indicated moderate agreement for grade I and II cartilage lesions (0.5), substantial agreement for grade III and IV cartilage lesions (0.70 and 0.66) and substantial agreement for normal regions (0.75). Regarding location of the cartilage lesions, Cohen’s kappa coefficient varied between almost perfect agreement in the lateral femoral condyle and no agreement in the trochlea.

In the setting of chronic ACL deficiency, MR imaging at 3.0 T achieves satisfactory diagnostic performance regarding meniscal and ligamentous pathology. In the detection of cartilage lesions MRI is less successful.