Group of Structural Mechanics and Materials Modelling, Aragón Institute of Engineering Research (I3A), Universidad de Zaragoza, Zaragoza, Spain.
Ann Biomed Eng. 2010 Mar;38(3):605-12. doi: 10.1007/s10439-009-9889-5. Epub 2010 Jan 6.
This work presents a portable non-invasive external fixator to assess and monitor fracture healing in real time. To evaluate the potential of this fixator, a transverse osteotomy was performed in the tibia of six adult sheep (mean age 3+/-0.5 years and weight 63+/-5 kg). The fractures were stabilized by a specially designed unilateral external fixator, which was instrumented by means of a set of strain gauges. Strains in the external surface of the fixator were monitored during all the healing process. A wireless, remote monitoring of the implant was developed through a specially designed external telemetric device. The strain gauges were arranged in two different half-bridge Wheatstone configurations, allowing easy post-processing of the signal. Thus, bending loads were measured in two planes of the external fixator acting as a load cell. The load through the fixator was evaluated for the gait cycle during all the healing process. Full weight bearing of the injured leg was observed from the beginning. The load transmission mechanism in the fixator was quite similar in all operated tibias and radiographic images showed a successful healing in all animals. Although the fixator has only been tested in an animal model, after further testing this system may have clinical potential.
本工作提出了一种便携式非侵入式外固定器，用于实时评估和监测骨折愈合。为了评估这种固定器的潜力，在 6 只成年绵羊（平均年龄 3+/-0.5 岁，体重 63+/-5 公斤）的胫骨中进行了横向截骨术。骨折通过专门设计的单侧外固定器固定，该固定器通过一组应变计进行了仪器化。在整个愈合过程中监测外固定器外表面的应变。通过专门设计的外部遥测设备开发了一种无线、远程植入物监测。应变计布置在两个不同的半桥惠斯通电桥配置中，允许对信号进行轻松的后处理。因此，弯曲载荷在作为负载细胞的外固定器的两个平面中进行测量。在整个愈合过程中，在步态周期中评估穿过固定器的负载。从一开始，受伤的腿就完全承受了体重。在所有操作的胫骨中，固定器的负载传递机制非常相似，并且所有动物的放射图像均显示出成功的愈合。尽管该固定器仅在动物模型中进行了测试，但经过进一步测试，该系统可能具有临床潜力。
