Developmental dysplasia of the hip

• evidence of developmental dysplasia of the right hip joint (DDH) with relatively small-sized right capital femoral epiphysis and shallow right acetabulum as well as superolateral displacement of the femoral head; it is located lateral to Perkin's line (vertical through lateral acetabular margin; should bisect middle third femoral metaphysis) and superior to Hilgenreiner's line (Drawn through right and left triradiate cartilage)

• increased right acetabular angle (more than 30 degrees)

• disturbed right Shenton's line

• normal left hip joint with normal acetabular angle, normal femoral head located medial to Perkin's line and inferior to Hilgenreiner's line as well as normal Shenton's line.

The dislocated femoral head lies superior and lateral to the intersection of the Hilgenreiner's and Perkin's lines. Note also the increased acetabular angle and disturbed Shenton's line on the left side.