The post-traumatic deformity resulting from the injury of the epiphyseal plate in the growing child is the matter of the great disaster in the orthopedic field and the prevention of those deformities is the important task for orthopedic surgeons. Several experimental studies on pathophysiology of bone bridge formation after growth plate injury have been reported but the prevention of it has been controversial.
To observe bone bridge formation after surgical manipulation for the injury of growing epiphyseal plate, forty-five rabbits weighing 700-1, OOOgm were divided into following 3 groups, each group comprising of 15 rabbits.
Group I : Injuries to the epiphyseal plate with Kirschner wire.
Group H : Transplantation of autogenous fat tissue into the defect of the injured epiphyseaI plate producedy by K-wire.
Group Interposition of medical silicone rubber implant into the defect of the injured epiphyseal plate produced by K-wire.
The animals were sacrificed at 2, 4, 6, 8 and 12 weeks after the experimental procedures and the histological examination of the injured epiphyseal plate of distal femur were made. The results obtained are as follows:
1. In group I , all fifteen cases started to form new osseous tissue from the fourth week, all of which developed to bone-bridge at the twelfth week between the metaphysis and the epiphysis.
2. In group U, transplanted fat tissue was mostly necrotized at the second week which was replaced with fibrous tissue between the second to the twlfth week. And the bone bridge was observed one case each at the fourth, sixth, and eighth week and two cases at the twelfth week.
3. In group 1, thirteen out of fifteen cases did not form bone bridge up to the twelfth week, and only thin bone bridge was observed one case each at the eighth and twelfth
week.
4. Prevention of bone bridge formation was ten out of fifteen cases (66.7%) in group II and thirteen out of fifteen cases (86.70) in group 1.
The above mentioned results clearly show that implant of the medical silicone rubber is better than autogenous fat tissue in preventing the bone bridge formation across the traumatized epiphyseal plate.
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