Braz J Phys Ther. 2013 May-Jun;17(3):263-71. doi: 10.1590/s1413-35552012005000090.
The application time of therapeutic ultrasound is an infrequently studied dosimetric variable that affects tissue repair.
The aim of this study was to evaluate the effects of different treatment times of therapeutic ultrasound (US) on the organization of collagen fibers in the tendons of rats.
Forty Wistar rats were selected (300±45 g), and the rats were divided into five groups (n=8 for each group): Control, without tenotomy or any treatment; tenotomy group, with tenotomy and without treatment; US groups (US1, US2, and US3), subjected to tenotomy and treated with US for one, two, or three minutes per area of the transducer, respectively. The animals were sacrificed on the 12th post-operative day, and the tendons were surgically removed for analyses of the collagen fiber organization by means of birefringence analysis.
The collagen fibers exhibited better aggregation and organization in the US3 group compared with the tenotomy group (p<0.05).
The findings suggest that US applied for three minutes per treated area improves the organization of collagen fibers during rat tendon repair.
治疗性超声波的应用时间是一个研究较少的剂量学变量，它会影响组织修复。
本研究旨在评估治疗性超声（US）不同治疗时间对大鼠肌腱胶原纤维组织的影响。
选择 40 只 Wistar 大鼠（300±45g），将大鼠分为五组（每组 n=8）：对照组，不进行肌腱切断术或任何治疗；肌腱切断组，进行肌腱切断术但不治疗；US 组（US1、US2 和 US3），在进行肌腱切断术的同时，分别对换能器的每个区域进行 1、2 或 3 分钟的 US 治疗。术后第 12 天处死动物，手术取出肌腱，通过双折射分析评估胶原纤维组织的排列情况。
与肌腱切断组相比，US3 组的胶原纤维表现出更好的聚集和组织排列（p<0.05）。
这些发现表明，每个治疗区域应用 3 分钟的 US 可改善大鼠肌腱修复过程中胶原纤维的排列。
