Type IIb, so called mobiled pseudoarthrosis according to Paley classification, is characterized by congenital pseudoarthrosis of proximal femur with an isolated small and stiff femoral head. We are unable to create a moveable hip joint but appropriate length of the affected extremity can be reached by gradual lengthening. In previous classification it is known as Type Aitken C or Pappas III. Type IIIa, with diaphysial deficiency of femur, corresponds to Type D according to Aitken or to Type I and II according to Pappas. In Type IIIa, the knee joint is developed and functional with the ROM more than 45 degrees. In Type IIIb the knee joint is more or less stiff and functionally unuseable. These three groups present the most severe congenital short femur deformities, but their occurrence is fortunately very seldom – less than 1 in 300 thousand live births. Among 41 cases of congenital short femur Pappas I–IV which were collected during 30 years from the Czech population of 10 million – Pappas I was seen in one case, Pappas II in five cases, Pappas III in 16 cases and Pappas IV in 19 cases. From the 16 cases of Pappas III deformity was found in three of them – stiffness of isolated femoral head was found and these three patients were added to this group.
Distraction of the distal part of femur up to acetabular level Connection between head and diaphysis First femoral lengthening Lengthening of the tibia Contralateral epiphysiodesis around the knee Plastic surgery Lengthening between 15 and 39 cm was reached. In Type IIIa, ilio-femoral fusion (knee-for-hip procedure) was performed in five cases. The functional results are excellent. There was no need for Syme amputation or rotationplasty. The prerequisite is at least 60 degrees arc of motion in the knee joint. Severe restricted ROM in the knee joint may lead to pseudoarthrosis. In Type IIIb (2 cases), the residual fragment of distal femur with unfunctional knee joint was stabilized in socket formed after pelvic osteotomy in the level of original acetabulum. The removal of telescopic proximo-distal movement stabilized the supportive function of the extremity.