Imaging Features of Bone Tumors: Conventional Radiographs and MR Imaging Correlation.

Imaging bone tumors often causes uncertainty, especially outside dedicated sarcoma treatment centers. Conventional radiography remains the backbone of bone tumor diagnostics, but MR imaging has a role. Radiographs are crucial for assessing the tumor matrix and aggressiveness. MR imaging is the best modality for local staging. This article reviews semiological aspects of bone tumors: patient age, tumor localization, pattern of bone destruction/margins, aggressiveness, growth speed, matrix formation, periosteal reaction, cortical involvement, size, and number of lesions. All aspects are discussed in terms of their appearance on radiographs and MR imaging, with a focus on the correlation between the 2 modalities.

Imaging of hip and thigh muscle injury: a pictorial review.

Muscle injuries of the hip and thigh are a highly relevant issue in competitive sports imaging. The gold standard in diagnostic imaging of muscle injuries is magnetic resonance imaging (MRI). Radiologists need to be familiar with typical MRI findings in order to accurately detect and classify muscle injuries. Proper interpretation of the findings is crucial, especially in elite athletes. In soccer players, muscle injuries of the hip and thigh are the most common reason for missing a game.The present pictorial review deals with the diagnostic assessment, especially MRI, of muscle injuries of the hip and thigh. Typical MR findings in muscle injuries include edema, hematoma, and tendinous avulsion as well as partial or complete muscle tear. To estimate the time to return to play, a grading into three groups-muscle strain, partial tear, complete tear-has traditionally been used. Taking into account the most recent literature, there are other prognostic factors such as the longitudinal length of a tear, the tendon's intramuscular component, or persisting edema.

Assessment of Loosening and Rotational Malalignment Following Knee Endoprosthesis or Other Surgical Components.

Total knee arthroplasty (TKA) has significant medical and economic implications. The correct placement of the femoral and tibial components is vital to ensure a functional knee and also low failure and revision surgery rates. This article provides the most relevant information regarding knee endoprosthesis from a radiologic point of view. Basic information on the recommended alignment of the femoral and tibial components in TKA and how to measure them are discussed. We then present the most important axial plane rotational references for the femoral and the tibial components. The optimal coronal alignment, illustrating the axes of the lower limb, and loosening as the major complication are also discussed. Finally, we offer a detailed example of rotational assessment.