Bone marrow aspirate concentrate (BMAC) is a potentially useful biological product for bone regeneration. This study investigated whether BMAC can be enriched by local minor corticotomies. Five 4-month-old domestic pigs were used with each pig undergoing two minor corticotomies at one randomly-selected tibia. Two weeks after the operation, bone marrow was aspirated from both tibiae and processed into BMAC samples. The amount of mesenchymal stem cells (MSCs) and the concentration of several regenerative growth factors contained in BMAC, as well as the proliferative and osteogenic differentiation capacity of MSCs, were compared between the corticotomy and the control sides. Another four weeks later, healing of the corticotomies was evaluated by radiographic and histological methods. The results demonstrated that BMAC from the corticotomy side contained significantly more MSCs than the control side. MSCs from the corticotomy side also proliferated significantly faster and tended to have stronger osteogenic differentiation than those from the control side. In contrast, the protein concentration of TGF-β, BMP-2 and PDGF contained in BMAC was only minimally changed by the corticotomies. The corticotomies in all pigs healed uneventfully, showing complete obliteration of the corticotomy gaps on CT images. Comparison between the two sides showed that the corticotomy side had thicker and denser cortical bone and more abundant osteogenic cell differentiation than the control side. These findings suggest that the quantity and proliferative/osteogenic differentiation capacity of MSCs contained in local BMAC can be enhanced by minor corticotomies, and spontaneous healing of the corticotomy can be completed within 6 weeks of the operation.

骨髓抽吸浓缩物（BMAC）是潜在有用的生物产物，可用于骨骼再生。这项研究调查了BMAC是否可以通过局部小切口皮层切开术进行充盈。使用五只4个月大的家猪，每只猪在一个随机选择的胫骨上进行两次小皮质切开术。手术两周后，从胫骨中吸出骨髓并处理成BMAC样品。比较了在皮质切开术和对照组之间的间充质干细胞（MSCs）的数量和BMAC中包含的几种再生生长因子的浓度，以及MSCs的增殖和成骨分化能力。再过四个星期，通过放射照相和组织学方法评估皮层切开术的愈合。结果表明，皮层切开术一侧的BMAC所含的MSC明显多于对照一侧。皮质切开侧的MSC增殖也明显快于成骨细胞，并且趋向于比对照侧更强。相反，BMAC中所含的TGF-β，BMP-2和PDGF的蛋白质浓度仅通过皮层切开术变化很小。所有猪的皮质切开术均愈合良好，在CT图像上完全清除了皮质切开间隙。两者的比较表明，与对照侧相比，皮质切开侧具有更厚和更密的皮质骨，并且更丰富的成骨细胞分化。