Current concept in dysplastic hip arthroplasty: Techniques for acetabular and femoral reconstruction

Figure 2 Left hip is normal, right hip is dysplastic. A: Crowe type 1-proximal head subluxation is less than 50% of vertical diameter of the femoral head (less than 10% of the pelvic height); B: Crowe type 2-proximal head subluxation is between 50% and 75% of vertical diameter of the femoral head (between 10% and 15% of the pelvic height); C: Crowe type 3-proximal head subluxation is between 75% and 100% of vertical diameter of the femoral head (between 15% and 20% of the pelvic height); D: Crowe type 4-proximal head dislocation with proximal movement of the femoral head for more than 100% of vertical diameter of the femoral head (head is moved proximally for more than 20% of the pelvic height).