Background: The biological plasticity of
the cartilaginous proximal part of the tibia in children makes it
possible to use the tibia to reconstruct the lower extremity after
excision of a sarcoma of the thigh. A type-B-IIIa rotationplasty
is an alternative to prosthetic replacement in very young children
who have a malignant tumor of the femur that requires extensive resection.
Methods: A type-B-IIIa rotationplasty was done
in eight patients who had a femoral tumor: four had a Ewing sarcoma;
three, an osteosarcoma; and one, a primitive neuroectodermal tumor.
The ages ranged from two years and eight months to ten years and six
months at the time of the procedure.
Results: All eight patients were able to bear
full weight and had a good range of motion of the hip joint at a
median of five years and one month (range, two years and four months
to eight years) postoperatively. They also were able to participate
in sports activities. Radiographs and magnetic resonance imaging
studies confirmed that the lateral part of the tibial plateau had
remodeled to form a structure that resembled a developing femoral
head. Seven patients were operated on only once, and a second hospital
stay was not necessary. The remaining patient had a prolonged hospitalization
for revision of the wound.
Conclusions: As an alternative to amputation
or an extendable tumor prosthesis, a type-B-IIIa rotationplasty
offers not only a better functional result but also biological reconstruction.
Placement of the cartilaginous head of the tibia into the acetabulum permits
development of a new femoral head. Thus, not only is the foot preserved
as a functional knee joint but a newly formed hip joint develops