[Taxonomy of congenital dislocation of the hip joint.].

In congenital dislocation of the hip joint the dislocation or subluxation of the hip joint is primary and so-called dysplasia of the acetabulum (of preluxation) or dysplasia of the proximal end of the femur (pathological anteversion) is secondary. So-called preluxation is only a variation of the normal state, the diagnosis of dysplasia of the acetabulum grade I is not based on any serious anatomical background. This is why the authors do not approve of repeated examinations of preluxations. In the prophylaxis of congenital dislocation of the hip joints the authors emphasize examination of neonates in maternity hospitals based on seeking of the so-called Ortolani or Barlow symptom. Key words: primary congenital dislocation, dysplasia of acetabulum is secondary.