In this study, multidetector CT showed a low sensitivity for other soft- tissue injuries at the knee; however, its high specificity indicated that apparent posterior cruciate ligament, meniscal, and collateral ligament tears can reliably be treated as true-positive findings [15]. The dual-energy CT virtual noncalcium technique can subtract calcium from cancellous bone, allowing detection [16-18] and possibly grading of the post-traumatic bone marrow contusions [18]. However, MRI is superior to CT in detection of bone marrow abnormalities and meniscal and ligamentous injuries and may be subsequently performed as clinically indicated. MR Arthrography Knee With negative radiographs, MR arthrography is not routinely used as the next imaging study for the evaluation of suspected occult knee fractures or internal derangement. MRA Knee With negative radiographs, MRA is not routinely used as the next imaging study for the evaluation of suspected occult knee fractures or internal derangement. MRI Knee MRI has many distinct advantages for the evaluation of the injured knee in the setting of negative radiographs. The majority of patients (93.5%) who present with acute knee injuries in the emergency department sustained soft- tissue injuries rather than osseous injuries [19]. MRI is a proven valuable tool in the treatment decision-making process, allowing earlier surgical intervention by obtaining a more accurate diagnosis [20,21]. Frobell et al [22] reported a low diagnostic benefit of the initial clinical examination in the setting of acute knee trauma with higher- than-suspected incidence of the ACL injuries on MRI. In randomized studies of patients with knee injuries [23,24], MRI findings shortened the diagnostic completion workup, reduced the number of additional diagnostic procedures, and improved quality of life in the first 6 weeks, potentially reducing productivity loss.
Acute Trauma to the Knee. In this study, multidetector CT showed a low sensitivity for other soft- tissue injuries at the knee; however, its high specificity indicated that apparent posterior cruciate ligament, meniscal, and collateral ligament tears can reliably be treated as true-positive findings [15]. The dual-energy CT virtual noncalcium technique can subtract calcium from cancellous bone, allowing detection [16-18] and possibly grading of the post-traumatic bone marrow contusions [18]. However, MRI is superior to CT in detection of bone marrow abnormalities and meniscal and ligamentous injuries and may be subsequently performed as clinically indicated. MR Arthrography Knee With negative radiographs, MR arthrography is not routinely used as the next imaging study for the evaluation of suspected occult knee fractures or internal derangement. MRA Knee With negative radiographs, MRA is not routinely used as the next imaging study for the evaluation of suspected occult knee fractures or internal derangement. MRI Knee MRI has many distinct advantages for the evaluation of the injured knee in the setting of negative radiographs. The majority of patients (93.5%) who present with acute knee injuries in the emergency department sustained soft- tissue injuries rather than osseous injuries [19]. MRI is a proven valuable tool in the treatment decision-making process, allowing earlier surgical intervention by obtaining a more accurate diagnosis [20,21]. Frobell et al [22] reported a low diagnostic benefit of the initial clinical examination in the setting of acute knee trauma with higher- than-suspected incidence of the ACL injuries on MRI. In randomized studies of patients with knee injuries [23,24], MRI findings shortened the diagnostic completion workup, reduced the number of additional diagnostic procedures, and improved quality of life in the first 6 weeks, potentially reducing productivity loss.