Effects of in vivo mechanical loading on large bone defect regeneration.
Effects of in vivo mechanical loading on large bone defect regeneration.
复制标题
DOI：
10.1002/jor.22042
复制
发表时间：
2012-07
影响因子：
2.8
通讯作者：
Guldberg, Robert E.
中科院分区：
文献类型：
--
作者：
Boerckel, Joel D.;Kolambkar, Yash M.;Stevens, Hazel Y.;Lin, Angela S. P.;Dupont, Kenneth M.;Guldberg, Robert E.
骨折愈合对力学条件高度敏感；然而，机械载荷对大骨缺损再生的影响尚未得到评估。在这项研究中，我们研究了功能负荷对临界尺寸节段性骨缺损修复的影响。在大鼠股骨中建立6mm的缺损，每个缺损接受5µg重组人骨形态发生蛋白-2 (rhBMP-2)，用海藻酸盐水凝胶递送。在研究期间，四肢用刚性固定板或从第4周开始允许压缩动态负荷转移的柔性固定板进行稳定。通过数字x线摄影、微计算机断层扫描、力学测试、组织学和有限元模型评估愈合情况。载荷显著增加再生骨体积和平均极惯性矩。加载响应与位置相关，缺陷近端极转动惯量增加，而远端没有。结果，弯曲钢板组的扭转刚度提高了58%，但破坏扭矩没有改变。在对每组的单个样本进行组织学评估时，与硬板组相比，负载组的软骨质量更大，板层骨的重塑程度更小。最后，通过有限元模型计算的主应变直方图显示，柔性板样品已经适应了更有效地在缺陷中分配载荷。总之，这些数据表明，轴向载荷的功能转移通过增加缺损内形成的骨的数量和分布来改变bmp诱导的大骨缺损修复。
Fracture healing is highly sensitive to mechanical conditions; however, the effects of mechanical loading on large bone defect regeneration have not been evaluated. In this study, we investigated the effects of functional loading on repair of critically sized segmental bone defects. Six-mm defects were created in rat femora, and each defect received 5 µg recombinant human bone morphogenetic protein-2 (rhBMP-2), delivered in alginate hydrogel. Limbs were stabilized by either stiff fixation plates for the duration of the study or compliant plates that allowed transfer of compressive ambulatory loads beginning at week 4. Healing was assessed by digital radiography, microcomputed tomography, mechanical testing, histology, and finite element modeling. Loading significantly increased regenerate bone volume and average polar moment of inertia. The response to loading was location-dependent with the polar moment of inertia increased at the proximal end of the defect but not the distal end. As a result, torsional stiffness was 58% higher in the compliant plate group, but failure torque was not altered. In single samples assessed for histology from each group, a qualitatively greater amount of cartilage and a lesser degree of remodeling to lamellar bone occurred in the loaded group compared to the stiff plate group. Finally, principal strain histograms, calculated by FE modeling, revealed that the compliant plate samples had adapted to more efficiently distribute loads in the defects. Together, these data demonstrate that functional transfer of axial loads alters BMP-induced large bone defect repair by increasing the amount and distribution of bone formed within the defect.
登录
查看更多内容
影响因子：
7.6
作者：
Alsberg, E;Kong, HJ;Mooney, DJ
通讯作者：
Mooney, DJ
影响因子：
5.3
作者：
Epari, Devakara R.;Kassi, Jean-Pierre;Duda, Georg N.
通讯作者：
Duda, Georg N.
影响因子：
5.6
作者：
Kanichai, Manoj;Ferguson, Damien;Campbell, Veronica A.
通讯作者：
Campbell, Veronica A.
影响因子：
12.4
作者：
Koefoed, M;Ito, H;Schwarz, EM
通讯作者：
Schwarz, EM
影响因子：
6.2
作者：
Guldberg, RE;Caldwell, NJ;Goldstein, SA
通讯作者：
Goldstein, SA