A total of 329 children with hip pain were examined by ultrasound, which indicated transient synovitis (n=161), rheumatoid arthritis (n=16), tuberculoid arthritis (n=3), septic arthritis (n=16), Legg-Calvé-Perthes disease (n=102), and slipped capital femoral epiphysis (n=31). Using the standard planes described by DEGUM and DGOOC, it is possible to analyze the joint capsule, the surface of the femoral head, and the periarticular structures.
In cases of synovitis or joint effusion, a capsular distension can be diagnosed by ultrasound. This distension is typical in transient synovitis, septic and tuberculoid arthritis, juvenile rheumatoid arthritis, and the onset phase of Perthes disease. Because capsular distension exhibits no significant differences in the various diseases, differentiation is not possible with ultrasound in the absence of osseous abnormalities. In cases with both capsular distension and osseous abnormalities, ultrasound usually allows a differentiation between slipped capital femoral epiphysis and Perthes disease as well as septic and unspecific arthritis.