Classifications There are typically four classes (or types) of<unk> , ranging from class A to class D, as detailed by Aitken. Types of<unk>  Type A — The femur bone is slightly shorter on the<unk>  end (near the hip), and the<unk>  head (the ball of the thigh bone that goes into the hip socket) may not be solid enough to be seen on X-rays at birth, but later hardens (ossifies). This deformity is sometimes called congenital short femur, because the child’s anatomy from hip to knee is contiguous and similar to their peers except for the one shortened bone. In some cases, children with type A deformities will also have an externally rotated femur, which could lead to bowing of the legs (genu varum). Type B — The femur bone is shorter on the<unk>  end (near the hip) and the defect affects both the<unk>  head (the ball) and the<unk>  shaft (the long part of the bone). This defect is more severe than type A deformities because it will not heal spontaneously and, at skeletal maturity, the<unk>  femur (lower part near the knee) will not connect with the<unk>  head. Type C — The entire top half of the femur bone is absent, including the trochanters (the part of the bone in which muscles are attached to the upper thigh), and the<unk>  head. In type C deformities, the<unk>  femur is not connected to the hip in any way. In fact, many children with type C deformities also have acetabular dysplasia, a condition in which the acetabulum (hip socket) is shallow, abnormally shaped, and oriented outward. Type D — This is the most severe form of<unk> , in which most of the femur bone is absent and only a small irregular piece of bone above the distal<unk>  epiphysis (the end of the femur bone at the knee) is present. In the pelvis, no acetabulum (hip socket) is present; instead the pelvic wall is flat on the affected side.
Proximal femoral focal deficiency
Bipartite patella
Luxating patella
Tarsal coalition
Radial dysplasia
Ankle fusion
Attenuated patella alta
Plantar calcaneal bursitis