[Ultrasonography-guided therapy].

Therapy for hip dysplasia and DDH by means of sonography. Numerous methods are available for treating "congenital" dysplasia of the hip (CDH). The important point seems to be the differentiation between dysplastic hip joints with and without displaced femoral heads. A historical review of the diagnosis of so-called "congenital dysplasia" and dislocation of the hip and different indications for therapeutic maneuvers is given. Generally, a three-step plan of treatment is recommended: dislocated heads must be reduced, after which retention is needed until the hip joint is stable. This is followed by maturation period, until the nonossified hyalin cartilagenous performed acetabular roof is ossified. All hip joints, regardless of age, can be assigned to one of these phases. In all cases, measures are taken to prevent ischemic necrosis of the femoral head. To prevent the residual dysplasia of the acetabulum roof and femoral head necrosis, the reduction-retention position should be more than 90 degrees flexion in the hip joint, but not more than 45-50 degrees abduction. In each therapeutic phase there is a different biomechanical situation in the hip joint. The appropriate orthosis for treatment is chosen according to the particular biomechanical situation. Each sonographic type can be set up according to the our classification in the three-phase treatment system. In this way the adequate orthosis for treatment in each treatment-phase can be chosen.