Imaging diagnosis of the articular cartilage disorders / 中华放射学杂志

ABSTRACT

Objective To evaluate the diagnosis and differential diagnosis among the chronic osteoarthritis, rheumatoid arthritis and other chronic cartilage lesions on the plain films and MR images. Methods Eighty-nine cases, including 115 joints, underwent plain film and MRI examination, and enhanced MRI scan was performed on 32 of them, including 44 joints. MRI scan sequences consisted of T 1WI, T 2WI+PDWI, STIR, and 3D FS SPGR. There were 90 knee joints in this group and each of the articular cartilage was divided into four parts patella, femoral medial condyle, femoral lateral condyle, and tibia facet on MR images. The cartilage disorders were classified according to the outerbridge method. In addition, 61 cases including 75 joints were observed as a control group on the plain films and MR images. Results 115 cartilage lesions were found on MR images, in which thinness of the cartilage (58 cases, 50 4%), bone changes under the cartilage (22 cases, 19.7%), medullar edema (22 cases, 19.7%), and synovial hyperplasia (52 cases, 45.2%) were seen. The patella cartilage was the most likely affected part (81/90, 90%). So the patellar cartilage lesions were divided as group 1 (grade Ⅰ-Ⅱ) and group 2 (grade Ⅲ-Ⅳ) on MR images, which were compared with the plain film signs. The narrowing of the joint space and saccules under the articular surface were statistically significant with each other, and ? 2 values were 9.349 and 9.885, respectively (P=0.002). Conclusion No constant signs could be seen on the plain films with grade Ⅰ-Ⅱ cartilage disorders. While the narrowing joint space and saccules under the joint surface could be seen on them with grade Ⅲ-Ⅳ cartilage disorders, which were mainly correlated with the cartilage disorders and bone changes under the articular cartilages. A combination of the plain films and MR images is the best imaging method for examining the joints and joint cartilages. Enhanced MRI scan is very helpful on the diagnosis and differential diagnosis of the synovial lesions.