Experimental epiphysiodesis: magnetic resonance imaging evaluation with histopathologic correlation.

We performed an experimental epiphysiodesis on the tibia in 16 immature New Zealand white rabbits. The purpose was to study the process of trauma-induced growth plate closure. The animals were killed at weekly intervals over 8 weeks. We correlated the histological findings with serial magnetic resonance images. The undamaged, central part of the growth plate became histologically abnormal within 1 week. Mature bone bridge formation in the area of the epiphysiodesis was seen after 3 to 4 weeks. The study suggests that growth arrest starts before the bone bridge formation. Factors regulating cartilage growth may also play a role.