[Abnormal joint laxity in hip dislocation during the first year of life. Arthrographic findings and prognosis].

247 cases of congenital dislocation of the hip (C.D.H.) with abnormal mobility of the hip joint were reviewed. Abnormal articular mobility (A.A.M.) was analyzed in 64 infants in whom the maneuvers described by Le Damany and Barlow were executed under arthrographic control. A.A.M. was caused by the deformity of the hip socket. The snapping sign was produced by the rise of the femoral capital epiphysis over the cartilaginous rim, in front of the limit separating the central, underformed part of the osseous acetabulum from its outer dysplastic portion. In eleven cases the "limbus" was located within the acetabular cavity, centrally with respect of the labrum. The Barlow sign was produced by the abnormal displacement of the femoral head within the incontinent and distorted hip socket. Prognostic factors were analysed in 161 patients reviewed older than one year.