Experimental study of bone lengthening by epiphyseal plate distraction

本研究旨在建立骨骺牵张骨延长动物模型，探讨骨骺牵张骨延长的成骨机制。为建立新的下颌骨牵张三维模型，将手指外固定装置固定于实验动物的上颌，克氏针固定于双侧下颌骨截骨后的下颌。用弹性橡皮筋将下颌骨向前牵引，观察到良好的骨形成。为探讨骨骺板牵张成骨的机制，在不截骨的情况下，用体外牵张器牵张兔股骨远端骨骺板。牵张10 d后，组织学观察显示，相对快速牵张（0.6mm/d）组软骨基质明显多于缓慢牵张（0.3mm/d）组。计划进行进一步的研究，如长期随访，评价骺板和骨的应力以及周围软组织的生长。

The aim of this study is to develop the rabbit model of bone lengthening by epiphyseal distraction and to investigate the mechanism of the bone formation in the epiphyseal distraction method. To develop the new three-dimensional mandibular distraction rabbit model, an external fixation device for finger was fixed to the upper jaw and Kirshner wire was set to the lower jaw of the experimental animal after bilateral osteotomy to the mandible. The mandible was distracted to forward with the elastic rubber bands and good bone formation was observed. For the investigation of the mechanism of the bone formation in the epiphyseal plate distraction, a rabbit distal femur epiphyseal plate was distracted with external distraction device without osteotomy. After 10days distraction, the histological findings revealed that much more cartilage matrix in relatively rapid distraction (0.6mm/day) group than slow distraction (0.3mm/day) group. Further investigation such as long-term follow-up, evaluation of stress to the epiphyseal plate and bone and surrounding soft tissue growth have been planning.