Kazemi M, Li L P, Buschmann M D, Savard P
Department of Mechanical and Manufacturing Engineering, University of Calgary, Calgary, AB T2N 1N4, Canada.
J Biomech Eng. 2012 Feb;134(2):021001. doi: 10.1115/1.4005764.
Partial meniscectomy is believed to change the biomechanics of the knee joint through alterations in the contact of articular cartilages and menisci. Although fluid pressure plays an important role in the load support mechanism of the knee, the fluid pressurization in the cartilages and menisci has been ignored in the finite element studies of the mechanics of meniscectomy. In the present study, a 3D fibril-reinforced poromechanical model of the knee joint was used to explore the fluid flow dependent changes in articular cartilage following partial medial and lateral meniscectomies. Six partial longitudinal meniscectomies were considered under relaxation, simple creep, and combined creep loading conditions. In comparison to the intact knee, partial meniscectomy not only caused a substantial increase in the maximum fluid pressure but also shifted the location of this pressure in the femoral cartilage. Furthermore, these changes were positively correlated to the size of meniscal resection. While in the intact joint, the location of the maximum fluid pressure was dependent on the loading conditions, in the meniscectomized joint the location was predominantly determined by the site of meniscal resection. The partial meniscectomy also reduced the rate of the pressure dissipation, resulting in even larger difference between creep and relaxation times as compared to the case of the intact knee. The knee joint became stiffer after meniscectomy because of higher fluid pressure at knee compression followed by slower pressure dissipation. The present study indicated the role of fluid pressurization in the altered mechanics of meniscectomized knees.
部分半月板切除术被认为会通过改变关节软骨和半月板的接触来改变膝关节的生物力学。尽管流体压力在膝关节的负荷支撑机制中起着重要作用，但在半月板切除力学的有限元研究中，软骨和半月板中的流体增压一直被忽视。在本研究中，使用膝关节的三维纤维增强多孔力学模型来探讨部分内侧和外侧半月板切除术后关节软骨中依赖于流体流动的变化。在松弛、简单蠕变和组合蠕变加载条件下考虑了六种部分纵向半月板切除术。与完整膝关节相比，部分半月板切除术不仅导致最大流体压力大幅增加，还使该压力在股骨软骨中的位置发生了偏移。此外，这些变化与半月板切除的大小呈正相关。在完整关节中，最大流体压力的位置取决于加载条件，而在半月板切除的关节中，该位置主要由半月板切除的部位决定。部分半月板切除术还降低了压力消散的速率，导致与完整膝关节相比，蠕变和松弛时间之间的差异更大。由于膝关节压缩时流体压力较高且随后压力消散较慢，半月板切除术后膝关节变得更僵硬。本研究表明了流体增压在半月板切除膝关节力学改变中的作用。
