The accuracy of MRI in the diagnosis of anterior cruciate ligament injury

BACKGROUND: Anterior cruciate ligament (ACL) injury can cause damage to the meniscus and articular cartilage, and may even lead to osteoarthritis. This study aimed to analyze the accuracy and feasibility of magnetic resonance imaging (MRI) imaging signs in the diagnosis of knee joint ACL injury. METHODS: A total of 78 patients admitted to our hospital from June 2018 to October 2019 with highly suspected ACL injury were selected for this prospective study. We used MRI and arthroscopy to diagnose the ACL injuries, and the results of MRI and arthroscopy, as well as the value of MRI in diagnosing ACL injury, were compared. RESULTS: Among the 78 participants, 66 cases were diagnosed with ACL injury (28 with complete tear, 38 with partial tear), and 12 were normal according to arthroscopy. Among the 66 cases with ACL injury, 63 (95.45%) were confirmed by MRI detection. The sensitivity, specificity, and accuracy of MRI in the diagnosis of ACL injury were 95.45% (63/66), 91.67%, and 94.87%, respectively. The accuracy of MRI in the diagnosis of complete and partial tears were 92.86% and 94.74%, respectively. Among the four direct MRI signs of ACL injury, the differences in interruption of ACL continuity, thickening and edema, and abnormal walking were statistically significant (P<0.05). Among the 8 indirect MRI signs, all showed high specificity and low sensitivity, and which the specificity of posterior cruciate ligament index, Notch sign, meniscus exposure sign of posterior ankle, and lateral collateral ligament monolayer display showed higher specificity (P<0.05). CONCLUSIONS: Examination with MRI offers high accuracy in the diagnosis of ACL injury, and has good consistency with arthroscopic diagnosis, which can provide reliable guidance for the selection and formulation of clinical surgery plans, and might be used as the first choice for the non-traumatic diagnosis of ACL injury.