Abstracts from the 1987 Annual Scientific Meeting at Vancouver, British Columbia Management of Hip Instability in Proximal Femoral Focal Deficiency
R. M. ETTS, MD, FRCS(C)*
Proximal femoral focal deficiency (PFFD) frequently presents difficult management problems. One of the unsolved problems is the provision of hip stability. There is probably no other deformity where the maxim "each patient must be treated individually" is more important. Some do very well with an unstable hip, whereas in others, this seems to be a major problem.
Using the Aitken classification, Type A PFFD usually does not present any problems with hip instability except where a pseudarthrosis has developed between the contained femoral head and the neck of the femur. In such instances, the defect may have to be grafted to ensure stability and, in other patients where the varus is extreme, valgus osteotomy may be required to improve gait. If the pseudarthrosis between the head and neck is profound and the shaft is riding high, it may be necessary to perform a varus osteotomy of the femur in order to provide stability and obtain fusion between the head and neck. In Type B, the acetabulum is dysplastic and the femur is displaced proximally with the head lying in the acetabulum. No ossification exists between the neck and head. Surgical stabilization of the hip necessitates fusion between the femoral shaft and head and may require an osteotomy. In most instances, however, this. is not necessary and a well fitting prosthesis will provide adequate stability. Types C and D deformities involve too much reconstruction of the hip to offer any significant advantages for hip stabilization. Hip fusion, hip arthroplasty, and the combination of acetabular reconstruction plus osteotomy of the femur do not provide enough advantages to warrant such surgery for most patients. The limbs are very short and should have knee fusion with a Syme's amputation in most instances. This usually corrects the flexed position of the hip and improves the alignment and stability of the hip. Proximal femoral focal deficiency taxes the ingenuity of both the prosthetist and the orthopaedic surgeon. It is essential that they work in concert to provide the most functional and practical management of the patient.
*Children's Hospital, University of Manitoba, 840 Sherbrook Street, Winnipeg, Manitoba R3A 1S1