Congenital Dislocation of the Hip

    Published Online:https://doi.org/10.1148/42.2.188

    There has never been a very general agreement as to the exact mechanism of congenital dislocation of the hip. It has been variously ascribed, to several developmental changes. One school holds that it is primarily a bone defect, the result of deficient development of the acetabulum with poor formation of the posterior rim. Others believe that it is due to a relaxation of the capsule and ligamentous structures, with secondary bone changes resulting from the lack of articulation. It is of interest, therefore, to find a new etiological concept described in a recent communication by Badgley (1). He is unable to correlate the clinical, embryological, and anatomical facts with a theory based on a primary fault inherent in the development of the acetabulum. He cannot understand how, if such a theory were correct, so large a percentage of patients with preluxation could go on to normal development after treatment. In a series of 478 cases of preluxation of the hip, treated in the first year of life by Putti's method of abduction and internal rotation of the hip, excellent results were obtained in 94 per cent.

    Badgley's contention is that the deformity is secondary to anteversion of the head and neck of the femur with a resultant secondary hypoplasia of the acetabulum. The chief evidence available of congenital dislocation of the hip in early embryonic life is to be found in arthrogryposis multiplex congenita, and for this reason a special study was made of that syndrome. The conclusion is reached that the characteristic posture of the limbs in arthrogryposis is definitely that of an arrest in development, with failure of normal rotation of the limb bud. The extrinsic and intrinsic factors producing this arrest must be assumed to be the marked muscle atrophy and degeneration and the rigidity of joints characteristic of this condition. The “secondary acetabulum” as described in these cases is not a true secondary acetabulum but actually represents a failure of development of the anterior margin of the ilium from pressure by the femoral head. Hypoplasia of the posterior superior margin of the acetabulum, which has been supposed to be the inherent acetabular defect in congenital dislocation, may well be due to similar pressure produced by anteversion of the head of the femur rotating the neck against the posterior acetabular rim. In further support of his theory, the author calls attention to a series of 500 cases of clubfoot, with evidence of dislocation of the hip in 39, and cites Böhm's theory of the embryological origin of clubfoot as an arrest of development of the hind foot which prevents its normal rotation.

    Badgley feels that there is an intrinsic design for the form of the acetabulum but that extrinsic forces play an increasing part in the later stages of development.

    Article History

    Published in print: Feb 1944