Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Shatin, Hong Kong, SAR, China.
Ultrasound Med Biol. 2011 Jul;37(7):1120-33. doi: 10.1016/j.ultrasmedbio.2011.04.017. Epub 2011 Jun 2.
Low-intensity pulsed ultrasound (LIPUS) was shown to have dose-dependent enhancement effect on the osteogenic activity of human periosteal cells that played an important role in fracture healing. It was hypothesized that the stimulatory effects of LIPUS on the periosteal cells could be optimized by adjusting the ultrasound delivered at its critical angle to the surface of bone. This increased the transmission of ultrasound waves on periosteum. By using a rat femoral fracture model, the stimulatory effects of LIPUS transmitted at 0°, 22°, 35° and 48°, and the sham-treatment control were investigated. Treatment efficacy was assessed using radiography, micro-computed tomography (micro-CT), histomorphometry and torsional test. The results showed that callus mineralization and bridging, biomechanical properties were significantly enhanced in the 35° group over the control and 0° groups after week 8. LIPUS transmitted at 35°, which could be the critical application angle, showed the best enhancement effects among all the other groups. LIPUS transmitted at a critical application angle may have greater enhancement effects in fracture healing.
低强度脉冲超声（LIPUS）对人骨膜细胞的成骨活性具有剂量依赖性增强作用，在骨折愈合中起着重要作用。研究假设通过调整作用于骨表面的临界角的超声，可以优化 LIPUS 对骨膜细胞的刺激作用，从而增加骨膜上超声波的传输。通过使用大鼠股骨骨折模型，研究了以 0°、22°、35°和 48°以及假处理对照的角度传输的 LIPUS 的刺激作用。使用射线照相、微计算机断层扫描（micro-CT）、组织形态计量学和扭转试验评估治疗效果。结果表明，在第 8 周后，与对照组和 0°组相比，35°组的骨痂矿化和桥接、生物力学性能显著增强。在所有其他组中，以临界应用角度传输的 LIPUS 显示出最佳的增强效果。在骨折愈合中，以临界应用角度传输的 LIPUS 可能具有更大的增强效果。
