Diagnostic Accuracy of Magnetic Resonance Imaging in the Diagnosis of Anterior Cruciate Ligament Injuries Using Arthroscopy as the Reference Standard

Abstract

Background: Anterior cruciate ligament (ACL) rupture is a common knee injury, particularly among young active individuals, and accurate diagnosis is essential for appropriate management. Magnetic resonance imaging (MRI), and arthroscopy are widely used diagnostic modalities, with arthroscopy considered the gold standard. Evaluating the diagnostic performance of MRI in comparison with arthroscopy remains clinically important for optimizing patient care. Aim of the study: To assess the diagnostic accuracy of MRI in anterior cruciate ligament ruptures by correlating their findings with arthroscopy as the gold standard. Patients and methods: Prospective cross-sectional diagnostic study was conducted at Imamein Kadhimein Medical City Baghdad, Iraq, between January 2024 and October 2025. Fifty adult patients with suspected ACL injury underwent MRI assessment, and arthroscopic evaluation. Arthroscopy was the gold standard. Results: The mean patient age was 29.6 ± 7.9 years, with males representing 82% of cases. Sports injuries were 48% of ACL injuries. Arthroscopy confirmed ACL tears in 45 patients (90%). MRI demonstrated 73.3% sensitivity, 75% specificity, PPV of 89.2%, NPV of 25%, and overall accuracy of 68%, also showing a significant association with arthroscopy (p < 0.001). MRI missed some ACL injuries confirmed arthroscopically. Conclusions: MRI have significant diagnostic value in ACL injury detection. Arthroscopy remains the definitive diagnostic modality. MRI may enhances diagnostic confidence before surgical intervention. Recommendations: MRI should be used as a complementary tool, particularly for evaluating associated intra-articular injuries. Arthroscopy is recommended when clinical suspicion persists despite inconclusive MRI findings.