Review Question - QID 4812

This individual has hip dysplasia and morphologic changes to her femoral head, which create an incongruent reduction of the femoral head in the acetabulum. Choosing the correct osteotomy is dependent on the presence of open growth plates and the type of femoral head coverage required. This patient is skeletally mature and has an incongruent reduction of the femoral head in the acetabulum on the abduction-internal rotation view. To obtain adequate coverage, a salvage operation such as a Chiari or Shelf is required.

Clohisey et al evaluated 16 hips in 13 patients with Severin IV or V hips (severe acetabular dysplasia) with hip pain who underwent a periacetabular osteotomy with very good results. However, all hip joints were congruent.

Ito et al. followed 170 hips after Chiari osteotomy for irreversible dysplasia for a mean of 20 years. Survivorship was calculated to be 85.7% at 30 years with total hip arthroplasty as an endpoint.

Figure A exhibits an AP pelvis of a skeletally mature female with closed triradiates, a dysplastic acetabulum and a subluxated hip with femoral head malformation. Illustration A exhibits an example of bilateral proximal femoral varus derotational osteotomies. Illustration B exhibits the cuts made in a Triple (Steele) osteotomy. Illustration C exhibits the cuts made in a Dega osteotomy. Illustration D exhibits the outcome after a Salter osteotomy. Illustration E exhibits the outcome after a Chiari osteotomy.

Incorrect answers:

Answer 1. Proximal femoral varus derotational osteotomy will not address the acetabular dysplasia
Answer 2. Periacetabular osteotomy requires joint congruency.
Answer 3. Dega osteotomy requires an open triradiate cartilage to provide a hinge. This patient's triradiate cartilage is closed.
Answer 4. Salter osteotomy typically is performed on younger patients with an open triradiate cartilage as it requires a flexible pubis to act as a hinge.