RABBIT GROWTH PLATE MORPHOLOGY IN TEMPORARY BILATERAL BLOCKING

Blocking of the growth plate (GP) using plates with screws (tension band plating) is a modern method used to correct deformities and moderate leg length discrepancy in growing children. Determining the duration of temporary bilateral blocking without the occurrence of irreversible changes of GP is of paramount importance important. Methods: Two-month-old Californian breed male rabbits (n=30) were exposed to bilateral blocking of the distal GP of the right femur locking plates with screws for 3, 5, and 7 weeks. The !xators were removed after 5 and 7 weeks in 18 rabbits and 3 weeks after that, animals were sacrificed. The contralateral limb was used as a control. Histological, histomorphometric, and X-ray analyses were performed. Results: During GP blocking, its height gradually decreased. This decreased was more pronounced after 7 weeks. Destructive changes progressed with an increase in the blocking duration. Three weeks after discontinuation of the bilateral blocking that lasted 5 weeks, the height of the GP significantly increased 1.2 times on the lateral side and 1.9 times on the medial side (p<0.001) compared to the control. When blocking was discontinued after 7 weeks, the structure of the GP was partially restored after 3 weeks, the height of GP significantly increased 1.2 times on the lateral side, and 1.07 times on the medial side (p<0.01) compared to the control. Conclusion: Restoration of the structural-functional features of the GP after the removal of the plates depends on the duration of temporary bilateral blocking, which must be taken into account in the clinical setting.