Low-intensity Pulsed Ultrasound Does Not Enhance Distraction Callus in a Rabbit Model

Abstract

Low-intensity pulsed ultrasound has been reported to have a positive effect when applied during the consolidation phase of distraction osteogenesis and bone transportation, but the optimal application time has not been determined. We used a rabbit model to determine whether low-intensity pulsed ultrasound applied during the distraction and early consolidation phases of tibial lengthening would have a positive effect on regenerated bone formation. Radiographic analysis showed no differences in regenerated callus area or in percent of callus mineralization between treated and control tibias immediately after distraction or at 1, 2, or 3 weeks after distraction. Similarly, we observed no differences in structural stiffness or maximal torque to failure at 1.5 or 3 weeks after distraction. We detected no differences in bone mineral appositional rates or percent tissue composition measured histologically between groups. Our data do not support the application of low-intensity pulsed ultrasound to regenerated bone during distraction osteogenesis.

Low Intensity Pulsed Ultrasound for Accelerating Distraction Osteogenesis: A Systematic Review of Experimental Animal Studies

“…These results can be explained by the fact that at early stages of DO, the distraction gap is filled mostly with hyper-cellular soft tissue and less mineralized tissue, thus facilitating the transmission of LIPUS. In contrast, the results in study [21] did not support the application of LIPUS at the distraction and early stages of consolidation periods.…”

“…Of which, 31 studies were eliminated after reviewing the abstracts which clearly showed these papers did not meet the criteria. Of the 19 potentially eligible articles retrieved in full text [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28], 2 were excluded as they used high intensity ultrasound (2 W/cm 2 ) [27,28] and 2 studies were published in 2 articles each and were thus considered as one study for the purpose of the research [11,12,23,24], leaving 15 eligible studies included in the systematic review (Fig. 1).…”

Extremely Small-magnitude Accelerations Enhance Bone Regeneration: A Preliminary Study

“…The benefit of the applied mechanical signal continued even during the 4-week rest period, perhaps suggesting the additional bone and vessels formed during the treatment period acted as a secondary resource for osteogenic and stem cells or the mechanism triggered by the signal remained active even after the stimulus had subsided [42]. The robust osteogenic effects of this noninvasive treatment observed after the 8-week experimental period also emphasizes some advantages over tissue-engineering approaches that rely on stem cells and/or physical signals such as ultrasound, electrical currents, or electromagnetic fields [1,11,28,43]. Not only is application of the physical signal noninvasive, simple, and inexpensive, it also does not require incubation time, bears no substantial risk of transmitting infections and diseases, and is unlikely to promote development of tumors from electrical waves.…”

“…Tissue-engineering approaches, including stem cells and growth factors [18,24] or externally applied signals such as stimulation with electric currents [7,11], ultrasound [10,43], or laser [28], are promising in overcoming these problems, but they also have several shortcomings. Current cell culture-based techniques require considerable resources to reach the number of required cells, bear risks for transfer of infectious diseases, and involve invasive surgery [40].…”

“…Current cell culture-based techniques require considerable resources to reach the number of required cells, bear risks for transfer of infectious diseases, and involve invasive surgery [40]. Many externally applied physical stimuli are clinically irrelevant, are inconvenient because of the complicated manner by which they are applied [30], or have shown inconsistent results [10,43].…”