Abstract：
BACKGROUND: The biomechanical environment created by suture-button fixation Latarjet is conducive to the healing and shaping of the transplanted coracoid, but its mechanism remains unclear. The latest research has found that the absence of stem cell chemokine (CXCL12) impeded bone regeneration in Sonic Hedgehog (SHH)-deficient animals. However, whether the biomechanical environment affects SHH and CXCL12 function has not been studied.
METHODS: Rat fracture models were constructed to simulate stress environments under non-load-bearing and load-bearing conditions. The fracture healing and shaping, as well as the expression levels of SHH and CXCL12, were assessed through gross viewing, micro-computed tomography (micro-CT), and histochemical staining.
RESULTS: Under flexible fixation, the relative bone volume (BV/TV) of rats exposed to the load-bearing stress environment was significantly higher than that of rats under a non-load-bearing stress environment (p ≤ 0.05). Adverse bone shaping was not observed in rats subjected to flexible fixation. The levels of SHH and CXCL12 in load-bearing rats exhibited significant elevation (p ≤ 0.05). Under a load-bearing stress environment, no significant difference was observed in the BV/TV between the flexible fixation group and the rigid fixation group (p ≥ 0.05), but there was excessive hyperplasia of the fracture callus in the rigid fixation group. The levels of SHH and CXCL12 in rats subjected to rigid fixation were significantly elevated (p ≤ 0.05).
CONCLUSIONS: Flexible fixation and load-bearing stress environment may contribute to bone healing and shaping by influencing the levels of SHH and CXCL12, suggested that this mechanism may be relevant to the healing and shaping of the transplanted coracoid after suture-button fixation Latarjet.
METHODS: Rat fracture models were constructed to simulate stress environments under non-load-bearing and load-bearing conditions. The fracture healing and shaping, as well as the expression levels of SHH and CXCL12, were assessed through gross viewing, micro-computed tomography (micro-CT), and histochemical staining.
RESULTS: Under flexible fixation, the relative bone volume (BV/TV) of rats exposed to the load-bearing stress environment was significantly higher than that of rats under a non-load-bearing stress environment (p ≤ 0.05). Adverse bone shaping was not observed in rats subjected to flexible fixation. The levels of SHH and CXCL12 in load-bearing rats exhibited significant elevation (p ≤ 0.05). Under a load-bearing stress environment, no significant difference was observed in the BV/TV between the flexible fixation group and the rigid fixation group (p ≥ 0.05), but there was excessive hyperplasia of the fracture callus in the rigid fixation group. The levels of SHH and CXCL12 in rats subjected to rigid fixation were significantly elevated (p ≤ 0.05).
CONCLUSIONS: Flexible fixation and load-bearing stress environment may contribute to bone healing and shaping by influencing the levels of SHH and CXCL12, suggested that this mechanism may be relevant to the healing and shaping of the transplanted coracoid after suture-button fixation Latarjet.
摘要：
背景：通过缝合按钮固定Latarjet创建的生物力学环境有利于移植的喙突的愈合和成形，但其机制尚不清楚。最新研究发现，缺乏干细胞趋化因子（CXCL12）会阻碍SonicHedgehog（SHH）缺陷动物的骨再生。然而,生物力学环境是否影响SHH和CXCL12功能尚未研究。
方法：构建大鼠骨折模型，以模拟非承重和承重条件下的应力环境。骨折愈合和塑形，以及SHH和CXCL12的表达水平，通过粗略观察进行评估，微型计算机断层扫描（micro-CT），和组织化学染色。
结果：在柔性固定下，暴露于负荷应力环境的大鼠的相对骨体积（BV/TV）明显高于非负荷应力环境下的大鼠（p≤0.05）。在进行柔性固定的大鼠中未观察到不利的骨成形。负重大鼠SHH和CXCL12水平显着升高（p≤0.05）。在承重应力环境下，柔性固定组与刚性固定组之间的BV/TV没有显着差异（p≥0.05），但刚性固定组骨折骨痂过度增生。刚性固定大鼠的SHH和CXCL12水平显着升高（p≤0.05）。
结论：柔性固定和承重应力环境可能通过影响SHH和CXCL12的水平来促进骨的愈合和成形，提示这种机制可能与缝合按钮固定Latarjet后移植的喙突的愈合和成形有关。
方法：构建大鼠骨折模型，以模拟非承重和承重条件下的应力环境。骨折愈合和塑形，以及SHH和CXCL12的表达水平，通过粗略观察进行评估，微型计算机断层扫描（micro-CT），和组织化学染色。
结果：在柔性固定下，暴露于负荷应力环境的大鼠的相对骨体积（BV/TV）明显高于非负荷应力环境下的大鼠（p≤0.05）。在进行柔性固定的大鼠中未观察到不利的骨成形。负重大鼠SHH和CXCL12水平显着升高（p≤0.05）。在承重应力环境下，柔性固定组与刚性固定组之间的BV/TV没有显着差异（p≥0.05），但刚性固定组骨折骨痂过度增生。刚性固定大鼠的SHH和CXCL12水平显着升高（p≤0.05）。
结论：柔性固定和承重应力环境可能通过影响SHH和CXCL12的水平来促进骨的愈合和成形，提示这种机制可能与缝合按钮固定Latarjet后移植的喙突的愈合和成形有关。
