Histological differences between various methods of hemiepiphysiodesis: is guided growth really different?

Traditional systems of hemiepiphysiodesis are based on the application of asymmetrical compression to the physis to correct angular deformities. The guided growth method claims to act as a tension plate avoiding compression. The aim of this study was to confirm or refute this claim. Twenty-four White New Zealand rabbits were subjected to a proximal tibial hemiepiphysiodesis using either staples or a plate and two-screws method. Both methods succeeded in producing deformity. The initial existent histological differences between systems became less apparent after 6 weeks of hemiepiphysiodesis, when histological results were very similar. The findings suggest that the eight-plate system produces, like staples, compression of the physis, but the forces are applied more gradually.