MRI Findings in Knee Trauma

"nMRI is the examination of choice for the evaluation of knee trauma. The use of a surface coil and thin-section high resolution scanning techniques in multiple planes has enhanced the depiction of structural details. This article reviews the MRI appearance of the normal knee anatomy and the role of MRI in the evaluation of knee trauma. The suggested protocol for the imaging of traumatic knee is coronal, sagittal and axial fast spin echo. At least one fat suppression sequence should be performed to rescale the contrast range and increase the conspicuity of soft tissue edema, fluid collection and bone marrow edema. The sagittal plane is generally the most effective for reviewing the internal derangement of the knee. Coronal imaging is necessary for the evaluation of the medial and lateral collateral ligament complex and axial imaging depicts the patellofemoral joint best. A meniscal tear is identified by an intrameniscal signal which extends to the joint surface. Tears in the anterior cruciate, posterior cruciate and collateral ligaments are also depicted. In this article we also evaluate the MRI findings of 100 patients with knee trauma and report the incidence of injury to different parts of the joint. The most common findings are joint effusion, meniscal injury and ACL tear. Some interesting cases of knee injuries are also shown.