Shakouri Kazem, Eftekharsadat Bina, Oskuie Mohammad Reza, Soleimanpour Jafar, Tarzamni Mohammad Kazem, Salekzamani Yagoub, Hoshyar Yousef, Nezami Nariman
Department of Physical Medicine and Rehabilitation, Tabriz University (Medical Sciences), Tabriz, Iran.
J Orthop Sci. 2010 Mar;15(2):240-4. doi: 10.1007/s00776-009-1436-6. Epub 2010 Apr 1.
Low-intensity ultrasound is a biophysical intervention on a fracture repair process. However, the effect of low-intensity ultrasound therapy on fracture healing is controversial. The aim of the present study was to evaluate the effect of low-intensity pulsed ultrasound (LIPUS) therapy on the fracture healing process, including mineral density and strength of callus using a rabbit model.
A total of 30 rabbits underwent unilateral, transverse, and mid-tibia open osteotomies that were stabilized with external fixators. Then, the animals were divided into two study groups composed of 15 rabbits each: the case group (US), which were exposed to low-intensity pulsed ultrasound with 30 mW/cm(2) intensity and 1.5 MHz sine waves; and the control group (C), which underwent sham ultrasound treatment. Callus development and mineral density were evaluated using multidetector computed tomography at 2, 5, and 8 weeks, after which the animals were killed. Three-point bending tests of both healed and intact bones were assessed and compared.
The results demonstrated that the callus mineral density in the US group was higher than in the C group (1202.20 +/- 81.30 vs. 940.66 +/- 151.58 HU; P = 0.001) at the end of the 8th week. The mean recorded three-point bending test score of healed bones in the US group was not significantly different from that of the C group (359.35 +/- 173.39 vs. 311.02 +/- 80.58 N; P = 0.114).
The present study showed that low-intensity pulsed ultrasound enhanced callus mineral density with an insignificant increase in the strength of the fractured bone.
低强度超声是一种作用于骨折修复过程的生物物理干预手段。然而，低强度超声治疗对骨折愈合的影响存在争议。本研究的目的是使用兔模型评估低强度脉冲超声（LIPUS）治疗对骨折愈合过程的影响，包括骨痂的矿物质密度和强度。
总共30只兔子接受了单侧、横向、胫骨中段开放性截骨术，并用外固定器固定。然后，将动物分为两个研究组，每组15只兔子：病例组（US），暴露于强度为30 mW/cm²、频率为1.5 MHz正弦波的低强度脉冲超声；对照组（C），接受假超声治疗。在第2、5和8周使用多排螺旋计算机断层扫描评估骨痂发育和矿物质密度，之后处死动物。对愈合骨和完整骨进行三点弯曲试验并进行评估和比较。
结果表明，在第8周结束时，US组的骨痂矿物质密度高于C组（1202.20±81.30 vs. 940.66±151.58 HU；P = 0.001）。US组愈合骨的平均三点弯曲试验评分与C组无显著差异（359.35±173.39 vs. 311.02±80.58 N；P = 0.114）。
本研究表明，低强度脉冲超声可提高骨痂矿物质密度，而骨折骨强度的增加不显著。
