Proximal Femoral Focal Deficiency: An Overview
ROBERT E. TOOMS, MD*
Aitken described this congenital skeletal limb deficiency as "a sharply localized absence of the proximal end of the femur involving the iliofemoral joint." Of the non-transverse terminal congenital limb deficiencies, PFFD is second in frequency only to fibular hemimelia. Over two-thirds of cases occur in association with fibular hemimelia; 15% are bilateral. Clinically, the typical deformity is a foreshortened lower limb held in a position of flexion, abduction, and external rotation, with the so-called "ship's funnel" appearance. Aitken has classified PFFD into four types: A and B have both a femoral head and an acetabulum, C and D do not demonstrate either a femoral head or an acetabulum. Most bilateral cases are type D. Differential diagnosis includes congenital coxa vara, congenital short femur, and phocomelia. Biomechanical deficiencies are limb-length inequality, malrotation, unstable hip joint, and inadequate proximal musculature. Treatment for unilateral cases may also be non-surgical with prostheses or may be surgical. If surgical treatment is elected, prosthetic fitting as a below-knee amputee may be achieved by performing Van Nes rotationplasty; treatment as an above-knee amputee is accomplished by ablating the foot with the option of performing a subsequent knee fusion. Hip surgery may be indicated in selected cases of types A and B.
*The Campbell Clinic, Inc., 869 Madison Avenue, Memphis, TN 38103-3422