Department of Physical Medicine and Rehabilitation, University of California, Irvine, Orange, CA, USA; Beckman Laser Institute, University of California, Irvine, CA, USA.
Beckman Laser Institute, University of California, Irvine, CA, USA; Department of Otolaryngology, Head and Neck Surgery, University of California, Irvine, Orange, CA, USA; Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, USA.
Clin Biomech (Bristol). 2020 Mar;73:92-100. doi: 10.1016/j.clinbiomech.2020.01.009. Epub 2020 Jan 15.
Electromechanical reshaping is a novel, minimally invasive means to induce mechanical changes in connective tissues, and has the potential to be utilized in lieu of current orthopedic therapies that involve tendons and ligaments. Electromechanical reshaping delivers an electrical current to tissues while under mechanical deformation, causing in situ redox changes that produce reliably controlled and spatially limited mechanical and structural changes. In this study, we examine the feasibility of altering Young's modulus and inducing a shape deformation using an ex vivo bovine Achilles tendon model.
Tendon was mechanically deformed in two different modes: (1) elongation to assess for tensile modulus and (2) compression to assess for compressive modulus. Electromechanical reshaping was applied to tendon specimens via flat plate platinum electrodes (6 V, 3 min) while simultaneously under mechanical strain for 15 min.
In elongation mode, post-electromechanical reshaping samples demonstrated a significant decrease in Young's modulus compared to pretreatment samples (66.02 and 45.12 MPa, respectively, p < 0.0049). In compression mode, posttreatment samples illustrated a significant shape change, with an increase in diameter (10.62 to 11.36 mm, p < 0.05) and decrease in thickness (4.13 to 3.62 mm, p < 0.05).
Results demonstrated a tissue softening effect without lengthening deformation during elongation, and a shortening effect without compromising compressive stiffness during compression. Electromechanical reshaping's reliable, low-cost, and efficacious methodology in inducing mechanical and structural connective tissue modifications illustrates a potential for future alternative orthopedic applications. Future studies will optimize and refine electromechanical reshaping to address clinically relevant geometries and methods such as needle techniques.
机电重塑是一种新颖的微创手段，可在不损伤组织的情况下诱导结缔组织的机械变化，并有可能替代目前涉及肌腱和韧带的骨科治疗方法。机电重塑在组织受到机械变形的同时施加电流，导致原位氧化还原变化，从而产生可靠控制和空间有限的机械和结构变化。在这项研究中，我们使用牛跟腱的离体模型来检验改变杨氏模量和诱导形状变形的可行性。
肌腱在两种不同模式下进行机械变形：（1）伸长以评估拉伸模量，（2）压缩以评估压缩模量。在 15 分钟的同时机械应变下，通过平板铂电极（6V，3 分钟）将机电重塑应用于肌腱标本。
在伸长模式下，与预处理样本相比，机电重塑后的样本的杨氏模量显著降低（分别为 66.02 和 45.12MPa，p<0.0049）。在压缩模式下，处理后的样本表现出明显的形状变化，直径增加（从 10.62 毫米增加到 11.36 毫米，p<0.05），厚度减小（从 4.13 毫米减小到 3.62 毫米，p<0.05）。
结果表明，在伸长过程中没有延长变形，而在压缩过程中没有降低压缩刚度，从而产生了组织软化效果。机电重塑在诱导机械和结构结缔组织改变方面具有可靠、低成本和有效的方法，表明其在未来骨科替代应用方面具有潜力。未来的研究将优化和改进机电重塑，以解决与临床相关的几何形状和方法，如针技术。
