I. Meniscus injury
Meniscus injury MRI is divided into three levels: grade I injury, which is early degeneration or degeneration; grade II injury, which is severe degeneration and is a continuation of grade I injury; grade III injury, which is tear (Menisci Tear), oblique tear, horizontal tear, vertical tear, radial tear, longitudinal tear, bucket-handle tear (BuckethandleTear), complex tear, and meniscal capsule separation.
Discoid Meniscus (Discoid Meniscus)
MRI-sag: 3 or more levels of the meniscus are connected at the anterior and posterior angles on a 5 mm layer thickness scan, forming a bow tie-like change.
Cor- The width of the narrowest part of the meniscus is greater than 14-15 mm, and the lateral edge is higher than the contralateral side by more than 2 mm.
II. Cruciate ligament injury
ACL: normal ACL starts from the anterior region of the intercondylar crest and goes upward and outward to the posterior aspect of the femoral epicondyle; PCL starts from the posterior region of the intercondyle and goes upward and outward to the posterior aspect of the femoral epicondyle MRI manifestation of cruciate ligament injury.
There are complete and partial tears in ACL injuries.
It is difficult to distinguish between partial and complete tears on MRI.
Direct signs of a complete ACL tear are.
Disruption of ACL continuity.
Distortion of the ligament in a wavy pattern.
formation of pseudotumors within the ACL with low signal on T1WI and high signal on T2WI, and incomplete fibrous tracts are seen.
Diffuse high signal in the ACL on T2WI.
Signs of posterior cruciate ligament rupture.
disruption of PCL continuity with regression and distortion of the residual ligament.
Absence of PCL on MRI.
Irregular high signal on T1WI, T2WI.
The PCL tibial attachment point has avulsed bone fragments and the posterior cruciate ligament is attached without disruption of ligament continuity.
Lateral collateral ligament injury
The normal anatomy of the lateral tibial collateral ligament starts below the medial femoral tuberosity and ends at the medial aspect of the tibia, corresponding to the level of the tibial tuberosity, with a length of about 11 cm and a width of about 1.5 cm The lateral fibular collateral ligament starts above the lateral epicondyle of the femur and ends below the head of the fibula, in the form of a round cord-like structure, with a length of about 5-7 cm.
On MRI, the normal collateral ligament is low-signal in any sequence, and the coronal and transverse axial planes are used to examine the lateral collateral ligament injury on MRI, which shows a complete rupture of the long T2 high signal within the ligament and a disruption of ligament continuity or thickening, swelling, and diffuse high signal within the ligament.
Fourth, patellar ligament injury
The normal anatomy is the continuation of the quadriceps muscle, which is one of the strongest ligaments in the body and is located directly in front of the knee capsule from the tip of the patella and the thick surface behind it, and ends at the tibial ridge, about 8 cm long.
The ligament is located anteriorly to the knee capsule from the patellar tip and its posterior rough surface down to the tibial ramus, and is approximately 8 cm long.
V. Quadriceps tendon