Welch R D, Birch J G, Makarov M R, Samchukov M L
Department of Research, Texas Scottish Rite Hospital for Children, Dallas 75219, USA.
J Bone Miner Res. 1998 Jan;13(1):1-9. doi: 10.1359/jbmr.1998.13.1.1.
Standardized histomorphometry of bone formation and remodeling during distraction osteogenesis (DO) has not been well characterized. Increasing the rhythm or number of incremental lengthenings performed per day is reported to enhance bone formation during limb lengthening. In 17 skeletally immature goats, unilateral tibial lengthenings to 20 or 30% of original length were performed at a rate of 0.75 mm/day and rhythms of 1, 4, or 720 times per day using standard Ilizarov external fixation and an autodistractor system. Two additional animals underwent frame application and osteotomy without lengthening and served as osteotomy healing controls. Histomorphometric indices were measured at predetermined regions from undecalcified tibial specimens. Within the distraction region, bone formation and remodeling activity were location dependent. Intramembranous bone formed linearly oriented columns of interconnecting trabecular plates of woven and lamellar type bone. Total new bone volume and bone formation indices were significantly increased within the distraction and osteotomy callus regions (Tb.BV/TV, 226% [p < 0.05]; BFR/BS, 235-650% [p < 0.01]) respectively, compared with control metaphyseal bone. Bone formation indices were greatest adjacent to the mineralization zones at the center of the distraction gap; mineral apposition rate 96% (p < 0.01); mineralized bone surfaces 277% [p < 0.001]); osteoblast surfaces 359% [p < 0.001]); and bone formation rate (650% [p < 0.01]). There was no significant difference (p < 0.14; R = 0.4) in the bone formation rate of the distracted callus compared with the osteotomy control callus. Within the original cortices of the lengthened tibiae, bone remodeling indices were significantly increased compared with osteotomy controls; activation frequency (200% [p < 0.05]); osteoclast surfaces (295% [p < 0.01]); erosion period (75%); porosity (240% [p < 0.001]). Neither the rhythm of distraction nor the percent lengthening appeared to significantly influence any morphometric parameter evaluated. Distraction osteogenesis shares many features of normal fracture gap healing. The enhanced bone formation and remodeling appeared to result more from increased recruitment and activation of bone forming and resorbing cells rather than from an increased level of individual cellular activity.
在牵张成骨（DO）过程中，骨形成和重塑的标准化组织形态计量学尚未得到很好的描述。据报道，增加每天进行的递增延长的节奏或次数可增强肢体延长过程中的骨形成。在17只骨骼未成熟的山羊中，使用标准的伊里扎洛夫外固定架和自动牵张器系统，以0.75毫米/天的速度和每天1次、4次或720次的节奏，将单侧胫骨延长至原始长度的20%或30%。另外两只动物进行了框架应用和截骨术但未延长，作为截骨愈合对照。从未脱钙的胫骨标本的预定区域测量组织形态计量学指标。在牵张区域内，骨形成和重塑活动取决于位置。膜内骨形成了由编织骨和板层骨相互连接的小梁板组成的线性排列的柱。与对照干骺端骨相比，牵张和截骨骨痂区域内的总新骨体积和骨形成指标分别显著增加（骨小梁骨体积/组织体积，226%[p<0.05]；骨形成率/骨表面积，235 - 650%[p<0.01]）。骨形成指标在牵张间隙中心的矿化区附近最大；矿化沉积率96%（p<0.01）；矿化骨表面277%[p<0.001]）；成骨细胞表面359%[p<0.001]）；以及骨形成率（650%[p<0.01]）。与截骨对照骨痂相比，牵张骨痂的骨形成率无显著差异（p<0.14；R = 0.4）。在延长胫骨的原始皮质内，与截骨对照相比，骨重塑指标显著增加；激活频率（200%[p<0.05]）；破骨细胞表面（295%[p<0.01]）；侵蚀期（75%）；孔隙率（240%[p<0.001]）。牵张的节奏和延长的百分比似乎均未显著影响所评估的任何形态计量学参数。牵张成骨具有正常骨折间隙愈合的许多特征。增强的骨形成和重塑似乎更多是由于骨形成和吸收细胞的募集和激活增加，而不是由于单个细胞活性水平的提高。
