Experimental study for vascularized bone graft with tissue engineering technique

骨缺损带血管骨移植比无血管骨移植有许多优点，但这些移植的可用性非常有限。带血管的骨移植物直径过小会引起骨折等并发症。髂骨和胫骨近端松质骨移植是预防血管化骨骨折的临床方法之一。但这些方法对供体部位的体积有限制。近年来，组织工程化骨技术得到了发展，并有临床应用的报道。组织工程骨放置的位置没有很好的记录。本研究的目的是观察F344大鼠血管化骨膜下和骨膜外组织工程骨移植的组织学和影像学变化。组织工程化骨放置于胫骨前骨膜下方或上方。在计算机断层扫描中，12个月后，移植骨的强度增加到皮质水平，18个月后保持与皮质骨相同的强度。骨膜下组骨膜上可见皮质骨结构。结果表明，骨膜下组织工程骨移植分为皮质骨和增加血管化骨移植体积的方法之一。

Skeletal bone defects with vascularized bone grafts has many advantages over non vascularized free grafts, but the availability of these grafts is extremely limited. Less of diameter in vascularized grafted bone caused several complication such as bone fracture. Cancelous bone graft from iliac bone and proximal of tibia were one of the clinical approach for prevent fractures of vascularized bone. but these methods has limitation of volume by donor site. Recently tissue engineered bone technique were developed and reported for clinical applications. Where the tissue engineered bone is placed is not well documented. The purpose of this study was to examine the histology and radiography of tissue engineered bone grafted under vascularized periosteum or over periosteum in F344 rats. Tissue engineered bone were placed in under or over periosteum of anterior tibia. In computed tomography, after 12 months, intensity of grafted bone increase to cortical level and maintain same intensity of cortical bone after 18 months. In under periosteum group, there were cortical bone structure right on the periosteum. the findings suggest that tissue engineered bone grafted under periosteum were divided to cortical bone and one of the method of increase the volume of vascuiarized grafted bone.