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The authors examined 10 patients treated by intra-articular reconstruction of the anterior cruciate ligament with an artificial ligament in terylene (Kejo-Leeds type). Clinical evaluation was supplemented by CT scan and magnetic nuclear resonance (M.R.). The basic parameters assessed were the positioning of the tunnels, biological anchoring, presence of reactive synovitis, growth and modification of periligamentous fibrous tissue, characteristics and relationships of the extra-articular plastic. CT scan was better at determining the tunnels, evaluating biological anchoring and visualising the new ligament in its intra-articular course. Magnetic nuclear resonance was better at evaluating changes in the periligamentous tissue. The authors therefore conclude that M.R. is preferable in the early follow-ups, while CT scanning has greater diagnostic value in follow-ups after six months.

An attempt was made to establish Magnetic Resonance Imaging (MRI) diagnostic criteria for the study of the reflex sympathetic dystrophy syndrome (RSDS). Five patients with hip and knee pain were studied. The radiographic pattern was "positive" only in two patients, while radionuclide studies showed increased activity in the painful joint in all; only in three cases Computed Tomography was performed. In all patients MRI demonstrates the lesions and defines their extension. MRI allows a differential diagnosis between RSDS and other bone lesions such as osteonecrosis and tumors. The relation between anatomopathological findings of RSDS and MRI features is discussed. MRI proved to be a reliable technique in showing and characterizing RSDS better than radiographic examination (often "negative" in early phases), and radionuclide study (a sensitive but not specific technique).

Twelve patients were studied by means of Magnetic Resonance Imaging (MRI) in order to demonstrate either loco-regional recurrence of central chondrosarcomas or degenerative evolutions of exostoses. MRI findings were compared with plain film, scintigraphy, and Computed Tomography. MRI showed loco-regional recurrences by demonstrating their site, extent, and relationship with adjacent structures. In showing the degenerative evolution of exostoses MRI--confirmed at surgery--was superior to plain film in 3 cases out of 7, and to Computed Tomography in 2 cases. The authors discuss MRI findings: chondrosarcomas have low-intensity signal in T1-weighted sequences and high-intensity signal in T2-weighted. Thanks to its high contrast resolution MRI always allowed the detection of the chondrosarcoma. Nevertheless, MRI did not allow the tumor grading--which is due either to a difficult evaluation of the morphology of neoplastic calcifications, or to non-specific-intensity signal.

Ten patients with squamous cell carcinomas located in the maxillo-facial region were studied. In all cases the staging by Computed Tomography (CT) and Magnetic Resonance (MRI) revealed metastatic lesions in stage T3-T4. All patients underwent polichemotherapy before surgery. MRI proved to be more accurate in the staging of tumors in 3 cases only, while in 7 cases both techniques showed the same diagnostic accuracy. In the follow-up, MRI allowed the evaluation of the effect of chemotherapy on the carcinomas: it demonstrated the regression and necrosis of 9 tumors out of 10 (the patients could undergo surgery), and the progression of the tumor in 1 case. The study of bioptic specimens demonstrated the lack of correlation between histological grading of the tumors with MRI signal intensity and T1, T2 relaxation time, as measured by spectroscopy.

MR imaging was employed in 232 patients with traumatic or degenerative lesions of the shoulder. MR diagnosis was compared with arthrotomic findings in 19 cases, and with arthroscopic results in 3 cases. MR technique is here presented and the choice of scanning planes is discussed, together with the sequences of image acquisition and with the features of the surface coil employed. Axial, sagittal, and coronal scans were used in all cases. Both sagittal and coronal planes were performed obliquely on the basis of precise anatomical structures. T1-weighted sequences were used for they are reliable in locating the various anatomical structures and efficient in defining the several different pathologic conditions. The role of T2-weighted sequences was complementary, and they were employed in selected cases only. A surface coil is presented with a particular configuration of easy clinical use and with such technical features as to allow reduced fields to be imaged, with good spatial resolution. MR imaging could demonstrate with equal accuracy both skeletal-cartilage components and capsulo-ligamentous structures, thus defining associated lesions and small tears. In both degenerative and traumatic lesions of the rotator cuff, MR imaging showed both extent and entity of the pathologic process, with high accuracy in defining the impingement syndrome. MR imaging allowed the depiction of the anterior and posterior glenoid labra, even without intraarticular contrast media. Moreover, MR imaging made it possible to recognize both fractures and degenerative processes within the glenoid labrum on the basis of their signal intensities. This preliminary experience allows the authors to conclude that MR imaging is an accurate and non-invasive diagnostic method for the study of traumatic lesions and of degenerative changes of the shoulder.

The value of Magnetic Resonance (MR) imaging was examined in the anatomical staging of bone osteosarcomas. Eleven patients were studied--8 central and 3 parosteal osteosarcomas. The accuracy of MR imaging was compared to that of plain film, scintigraphy, CT, and angiography. MR imaging was superior to both CT and radionuclide scanning in defining intramedullary extension and in showing skip metastases. Cortical erosion in central osteosarcomas was demonstrated by MR imaging, CT, and plain film; in 1 case of parosteal osteosarcoma MR imaging was superior to CT in showing cortical penetration. In two cases MR imaging did not accurately demonstrate the relationship of the tumor to the major vessels; only angiography showed vascular involvement. MR imaging was useful in delineating extraosseous extension. The importance is stressed of a correct use of MR imaging towards an accurate diagnosis. In fact, intramedullary extension and skip metastases were better demonstrated on T1-weighted images with large fields, while T2-weighted images and small fields were needed for the best overall evaluation of extraosseous involvement. In conclusion, MR imaging should be used for preoperative staging of osteosarcomas in those cases where diagnosis was made on the basis of clinical, radiographic, and bioptic findings.