Department of Anatomy & Cell Biology, Rush University Medical Center, 600 South Paulina, Suite 507, Chicago, IL 60612, USA.
J Orthop Res. 2013 May;31(5):800-6. doi: 10.1002/jor.22294. Epub 2012 Dec 31.
To examine bone remodeling following implant placement, 88 female Sprague-Dawley rats underwent either sham ovariectomy (sham-ovx) or ovariectomy (ovx) at 4.5 months. At 11 months, 17 baseline control animals were euthanized, while 71 rats received bilateral intramedullary femoral implants. Implanted rats were randomized to 4-, 8-, or 12-week follow-up times. Microcomputed tomography was used to assess cortical area and trabecular architecture in all rats. Dynamic and static histomorphometry were performed in a subset to examine the trabecular and endocortical bone in the distal femoral metaphysis adjacent to the implant and the periosteal surface at the midshaft superior to the implant (n = 59). Implantation did not affect bone volume in either sham-ovx or ovx rats compared to baseline controls. Implant placement significantly increased mineralizing surface, mineral apposition rate, and bone formation rate in both sham-ovx and ovx rats at the trabecular and endocortical surfaces at four and sometimes 8 weeks, with a return to baseline values by 12 weeks. At the periosteal surface, implant placement increased bone formation at 4 weeks with a return to baseline levels by 8 weeks. Thus, implant placement increases bone remodeling transiently without affecting bone volume in sham-ovx and ovx rats.
为了研究种植体植入后骨重建情况，将 88 只雌性 Sprague-Dawley 大鼠在 4.5 个月时行假卵巢切除术（sham-ovx）或卵巢切除术（ovx）。11 个月时，处死 17 只基线对照动物，其余 71 只大鼠接受双侧髓内股骨植入物。植入大鼠随机分为 4、8 或 12 周随访时间。所有大鼠均采用微计算机断层扫描评估皮质面积和小梁结构。对一部分大鼠进行动态和静态组织形态计量学检查，以检查植入物附近股骨远端骺和皮质内骨以及植入物上方骨干中部骨表面的小梁和骨内表面（n=59）。与基线对照组相比，植入物植入对 sham-ovx 和 ovx 大鼠的骨体积均无影响。植入物植入显著增加了 sham-ovx 和 ovx 大鼠的小梁和皮质内表面的矿化表面、矿化沉积率和骨形成率，在 4 周和有时 8 周时达到峰值，12 周时恢复到基线值。在骨表面，植入物在 4 周时增加骨形成，8 周时恢复到基线水平。因此，植入物植入会短暂增加骨重建，但不会影响 sham-ovx 和 ovx 大鼠的骨体积。
