[Knee problems--imaging techniques].

Abstract

Standard radiographs still represent the standard imaging method in knee abnormalities. Major advantages include high spatial resolution, low cost, high availability and standardized imaging technique. Because there is an increasing pressure on the cost of health care, additional imaging should only be employed based on a working hypothesis. In most cases MR imaging is most suitable for further diagnosis. In internal knee derangements MR imaging has been shown to have a high negative predictive value, thus obviating unnecessary surgery. MR imaging also is the imaging method of choice in the detection and follow-up of arthritis, in the detection, staging and follow-up of malignant neoplasms, and in the detection of occult fractures. Ultrasonography is useful in the characterization of superficial soft-tissue abnormalities, but has not gained high acceptance in searching for internal derangements of the knee. Scintigraphy is competing with MR imaging in the early detection of bone abnormalities and for follow-up. However, it is less expensive and can be employed for the evaluation of multilocular processes. CT has a limited role in the evaluation of complex fractures mainly of the tibial plateau.