Effect of excising various scale of the Ranvier's groove on the development of epiphyseal plate

Objective: To explore the effect of excising various scale of the Ranviefs groove on the development of epiphyseal plate in circumference. Methods: The proximal growth plates of the tibias were exposed in young rabbits, and then the Ranvier's grooves and fibrous covers were removed at the length of 4 mm and 12 mm respectively. The percentage of excised area was estimated and the epiphyseal were anatomically and histologically evaluated. Results: Percentages of injured growth plates were (12. 5±0. 09) % and (37. 50±0. 20) % respectively in the 4 mm and 12 mm group. After 8, 12 weeks, shortening of tibia in the 12 mm group was (0. 97±0. 49) ,(2. 78±0. 46) mm and enlarging tibia angle(10. 867±1. 354), (16. 608±1. 080) degree, whereas none was observed in the 4 mm group (P<0. 05). Histological studies showed that proliferation zone became thicker, the bony-bridge began to form four weeks postoperatively. Bone bridge spanned the growth the growth plate on the 8th week and enlarged in size on the 12th week, respectively. In the 12 mm group, proliferation zone next to the bony-bridges became thinner and no growth retardation was found in 4 mm group. Conclusion: Epiphyseal plate retardation secondary to a excising injury of the Ranvier's groove is related to the percentage of the injured scale. If the scale> 12. 5%, the bone growth in width may be retarded. Ranvier's groove is responsible for inhibition the bone growth in circumference.