[The painful hip--diagnostic possibilities of sonography]

205 patients with a painful hip joint have been investigated prospectively. The examination technique and the sonoanatomy of the hip joint are illustrated. An intraarticular effusion could be detected in 105 patients. Depending on the aetiology and the duration of disease, different echostructures of the fluid collections were noted. Additionally, the reaction of the synovia and of the articular capsule allowed the discrimination of transient synovitis and septic arthritis. Extraarticular alterations were found in 11, changes of the bone contour in 40 patients (osteomyelitis, slipping femoral epiphysis, or Perthes-Calvé disease). Sonography is recommended as method of choice in excluding, confirming and differentiating intraarticular effusions. Intra- and periarticular affections can be distinguished safely. Bone alterations may be detectable as well.