运用渗透性膨胀和超声显微成像弹性技术研究关节软骨的力学特性

Study on Elasticity of Articular Cartilage using Osmosis-Induced Swelling and Ultrasound Elastomicroscopy

关节软骨是覆盖在关节骨表面的重要承重组织,其结构与成分的变化均会造成软骨的退化,从而最终导致骨关节炎等疾病的发生,因此研究关节软骨的力学性质具有重要意义。该研究通过改变关节软骨外溶液的离子浓度引起软骨的渗透性膨胀行为,结合超声显微弹性成像技术,依据超声回波计算得到软骨不同深度的位移变化量,绘制软骨内部组织弹性成像并预测了随深度变化的软骨轴向模量。该研究表明利用超声显微弹性成像技术可以有效观测软骨内部由渗透压力引起的膨胀行为,并可以描述关节软骨的力学性质,为研究关节软骨早期病变提供一个有效可行的方法。

Articular cartilage is important weight-bearing connective tissue covering the articulating bony ends in diarthrodial joints.The structural or component changes of articular cartilage induce degenerations of the tissue and consequently cause osteoarthritis （OA）.In this study,we used osmosis loading to induce swelling behavior of articular cartilage and apply ultrasound elastomicroscropy to map the depth-dependent deformations in the tissue.The intrinsic layered material parameters of the articular cartilage were extracted using a triphasic model.Results showed that the ultrasound elastomicroscropy system could investigate the mechanical properties of articular cartilage associated with osmosis-induced swelling behavior of articular cartilage in a non-contact way.This method could be potential to assess the progressive degeneration of cartilage for the early diagnosis of OA.