Pedicled scapular apophysis transplantation. Growing grafts studied in dogs

Twenty-eight immature dogs, divided into three groups, have been studied to determine the possibilities of pedicled epiphyseal transplantation from a rarely used donor site area, the scapula. One group of 8 immature dogs were studied anatomically using India ink and Batson's compound injection methods. We identified the vascular pattern of the diaphyseal portion of the graft, consisting of the lateral crest or border of the scapula. In two groups of 10 immature dogs, this area was used as a pedicled island graft to rebuild the semiresected or totally resected proximal humerus. There were marked differences between these two groups on the basis of morphologic, histologic, histochemical and electron microscopic aspects of the samples. Preservation of normal growth appeared to be directly related to the compressive forces applied to the graft. Preservation of the cartilage was also related to the biomechanical situation; fibrocartilage and signs of arthrosis were noted 1 year after the operation in several animals whose humeri had been fully subjected to normal stresses. Both the diaphyseal and epiphyseal areas had increased one- to fivefold in volume, but longitudinal growth was markedly deficient.