Abstract:Objective: To evaluate the relationship between medial meniscus subluxation and knee injury by MRI. Methods: Knee MRI of 77 patients with medial meniscus subluxation was analyzed retrospectively. Results: ①Ligament injury: 26 cases had anterior cruciate ligament rupture(4 complete rupture and 22 partial rupture), with a consistency of 88.8% with the arthroscopic diagnosis; 26 cases had posterior cruciate ligament rupture(3 complete rupture and 23 partial rupture), with a consistency of 95.0% with the arthroscopic diagnosis; 17 cases had medial collateral ligament injury(1 grade Ⅲ, 13 grade Ⅱ and 3 grade Ⅰ injury); 13 cases had lateral collateral ligament injury(8 grade Ⅱ and 5 grade Ⅰ injury), with a consistency of 90.0% with the arthroscopic diagnosis. ②Meniscus injury: 73 cases had medial meniscus injury(50 degree Ⅲ, 13 degree Ⅱ and 10 degree Ⅰ injury); 30 cases had lateral meniscus injury(10 degree Ⅲ, 8 degree Ⅱ and 12 Ⅰ degree injury), with a consistency of 90.5% with the arthroscopic diagnosis; 46 cases had posterior root injury of the medial meniscus, with a consistency of 92.21% with the arthroscopic diagnosis. ③Cartilage damage: 68 cases had cartilage damage(1 grade 4, 21 grade 3, 46 grade 2 damage), with a consistency of 73% with the arthroscopic diagnosis. ④Bone hyperplasia: 40 cases had osteophyte formation. Conclusion: Medial meniscus subluxation is an important indirect sign of ligament injury, meniscus injury, cartilage injury and osteoarthritis. MRI diagnosis of medial meniscus subluxation is significant for the detection of knee injuries, and can effectively prevent knee osteoarthritis initiation and progress.