Aronson J, Shen X C, Skinner R A, Hogue W R, Badger T M, Lumpkin C K
Department of Orthopaedics, University of Arkansas for Medical Sciences, Little Rock, USA.
J Orthop Res. 1997 Mar;15(2):221-6. doi: 10.1002/jor.1100150210.
Prior studies of distraction osteogenesis in dog and rabbit models have shown predominantly intramembranous bone formation. Other models of fracture healing normally display mixtures of both endochondral and intramembranous bone formation. We have established a rat model of tibial lengthening that reliably reproduces the pattern of zonal osteogenesis previously observed in dog and rabbit models. A distraction rate of 0.25 mm twice a day with a 0-day latency period produced intramembranous bone with zones of progressive mineralization from collagen. With this protocol, rats bridged the distraction gap with a 25% increase in the tibial bone length. After 20 days of distraction and 50 days of consolidation, the three-point bending stiffness, as a percentage of the contralateral control, reached a level equivalent to that measured in the canine model for a 15% lengthening (28-day distraction and 84-day consolidation). Radiodensitometric analysis of the regenerate bones measured 97% of the unaffected contralateral tibial densities, and mineral analyses demonstrated that calcium and phosphorus levels in the regenerate bone reached 78% of contralateral tibial levels by day 70. We concluded that a rat model of distraction osteogenesis will be useful for a wide range of studies involving rapid intramembranous bone formation.
先前在狗和兔子模型中进行的牵张成骨研究主要显示为膜内成骨。其他骨折愈合模型通常同时显示软骨内成骨和膜内成骨。我们建立了一种大鼠胫骨延长模型，该模型能够可靠地重现先前在狗和兔子模型中观察到的区域性成骨模式。每天两次以0.25毫米的牵张速率，潜伏期为0天，可产生从胶原蛋白开始逐渐矿化区域的膜内成骨。按照此方案，大鼠填补了牵张间隙，胫骨长度增加了25%。在牵张20天和巩固50天后，三点弯曲刚度相对于对侧对照的百分比达到了与犬类模型中15%延长（牵张28天和巩固84天）时测量的水平相当。对再生骨的放射密度分析测得其密度为未受影响的对侧胫骨密度的97%，矿物质分析表明，到第70天时，再生骨中的钙和磷水平达到对侧胫骨水平的78%。我们得出结论，牵张成骨大鼠模型将有助于开展涉及快速膜内成骨的广泛研究。
