Study of development in an experimental animal model of a pediatric physeal slide-traction plate.

Background: To develop a physeal slide-traction plate for children can provide rigid internal fixation of a bone fracture without inhibiting epiphyseal growth.
Methods: The slide-traction plates and standard plates were designed to configure to the femoral condyle. Twelve of thirty goats were used as normal controls and the rest were implanted with plates (right femurs were fixed with standard plates, and left femurs were fixed with slide-traction plates). All goats underwent X-ray examination at 1 month, 3 months and 6 months after surgery, and femoral length were measured. Histological staining and electron microscopy were performed to evaluate the development of the epiphyseal plate at 3 and 6 months after surgery.
Results: Compared to the standard plate, the slide-traction plate group exhibited more normal physeal growth, histologic features, safranin O staining, and electron microscopy structural features. There were significant differences in length in the femurs of goats fixed with slide-traction plates and standard plates at 1 month, 3 months, and 6 months after surgery, respectively. There was no difference between femurs of the normal control group and the femurs fixed with the slide-traction plates. Thicker epiphyseal plates were found in the left vs. the right femurs of the group fixed with plates at 3 and 6 months after surgery. In the group fixed with plates, Safranin O staining showed that the epiphyseal plates of the left femurs had more fuscous staining than the right femurs at 3 and 6 months after surgery. Electron microscopy also showed that cells in the epiphyseal plates of the left femurs were healthier in appearance than cells from the right femurs in the group fixed with plates.
Conclusion: The physeal slide-traction plate can slide with the growth of the physis and is suitable for fixation of fractures in this region.