Mukherjee N, Wayne J S
Department of Biomedical Engineering, Virginia Commonwealth University, Richmond 23298-0694, USA.
J Biomech Eng. 1998 Oct;120(5):614-9. doi: 10.1115/1.2834752.
The in situ mechanical conditions of cartilage in the articulated knee were quantified during joint loading. Six porcine knees were subjected to a 445 N compressive load while cartilage deformations and contact pressures were measured. From roentgenograms, cartilage thickness before and during loading allowed the calculation of tissue deformation on the lateral femoral condyle at different times during the loading process. Contact pressures on the articular surface were measured with miniature fiber-optic pressure transducers. Results showed that the medial side of the lateral femoral condyle had higher contact pressures, as well as deformations. To begin to correlate the pressures and resulting deformations, the intrinsic material properties of the cartilage on the lateral condyle were obtained from indentation tests. Data from four normal control specimens indicated that the aggregate modulus of the medial side was significantly higher than in other areas of the condyle. These experimental measures of the in situ mechanical conditions of articular cartilage can be combined with theoretical modeling to obtain valuable information about the relative contributions of the solid and fluid phases to supporting the applied load on the cartilage surface (see Part II).
在关节加载过程中，对膝关节内软骨的原位力学状况进行了量化。对六个猪膝关节施加445 N的压缩载荷，同时测量软骨变形和接触压力。通过X线片，加载前和加载过程中的软骨厚度使得能够计算加载过程中不同时间外侧股骨髁处的组织变形。用微型光纤压力传感器测量关节表面的接触压力。结果表明，外侧股骨髁的内侧具有更高的接触压力以及变形。为了开始关联压力和由此产生的变形，通过压痕试验获得了外侧髁软骨的固有材料特性。来自四个正常对照标本的数据表明，内侧的聚集模量显著高于髁的其他区域。这些关节软骨原位力学状况的实验测量结果可与理论模型相结合，以获得关于固相和液相在支撑软骨表面施加的载荷方面相对贡献的有价值信息（见第二部分）。
