Extracorporeal shock wave therapy (ESWT) has been demonstrated to accelerate bone healing; however, the mechanism underlying ESWT-induced bone regeneration has not been fully elucidated. This study aimed to examine the effects of ESWT and the process of fracture healing. A rat model of femur delayed-union was established by cauterizing the periosteum. ESWT treatment at the fracture site was performed 2 weeks after the operation and the site was radiographically and histologically evaluated at weeks 4, 6, and 8. The bone union rate and radiographic score of the ESWT group were significantly higher than those of the control group at 8 weeks. Histological evaluation revealed enhanced endochondral ossification at the fracture site. The effects of ESWT on ATDC5 cells were examined in vitro. ESWT promoted chondrogenic differentiation without inhibiting the proliferation of ATDC5 cells. ESWT may induce significant bone healing by promoting endochondral ossification at the fracture site.

体外冲击波疗法（ESWT）已被证明可以加速骨骼愈合。但是，尚未完全阐明ESWT诱导的骨再生的机制。这项研究旨在检查ESWT的效果和骨折愈合的过程。通过烧灼骨膜建立大鼠股骨延迟愈合模型。术后2周在骨折部位进行ESWT治疗，并在第4、6和8周进行影像学和组织学评估。ESWT组的骨结合率和影像学评分明显高于对照组在8周。组织学评估显示骨折部位软骨内骨化增强。在体外检查了ESWT对ATDC5细胞的作用。ESWT促进软骨形成分化，而不抑制ATDC5细胞的增殖。ESWT可通过促进骨折部位的软骨内骨化来诱导明显的骨愈合。